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WO2014188756A1 - Optical sensor and display apparatus - Google Patents

Optical sensor and display apparatus Download PDF

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Publication number
WO2014188756A1
WO2014188756A1 PCT/JP2014/055606 JP2014055606W WO2014188756A1 WO 2014188756 A1 WO2014188756 A1 WO 2014188756A1 JP 2014055606 W JP2014055606 W JP 2014055606W WO 2014188756 A1 WO2014188756 A1 WO 2014188756A1
Authority
WO
WIPO (PCT)
Prior art keywords
light
light receiving
receiving element
optical sensor
photocurrent
Prior art date
Application number
PCT/JP2014/055606
Other languages
French (fr)
Japanese (ja)
Inventor
井上　高広
佐藤　秀樹
浩一朗 杉本
Original Assignee
シャープ株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by シャープ株式会社 filed Critical シャープ株式会社
Publication of WO2014188756A1 publication Critical patent/WO2014188756A1/en

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Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03K—PULSE TECHNIQUE
    • H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
    • H03K17/94—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the way in which the control signals are generated
    • H03K17/941—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the way in which the control signals are generated using an optical detector
    • H03K17/943—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the way in which the control signals are generated using an optical detector using a plurality of optical emitters or detectors, e.g. keyboard
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J1/00—Photometry, e.g. photographic exposure meter
    • G01J1/02—Details
    • G01J1/04—Optical or mechanical part supplementary adjustable parts
    • G01J1/0407—Optical elements not provided otherwise, e.g. manifolds, windows, holograms, gratings
    • G01J1/0411—Optical elements not provided otherwise, e.g. manifolds, windows, holograms, gratings using focussing or collimating elements, i.e. lenses or mirrors; Aberration correction
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J1/00—Photometry, e.g. photographic exposure meter
    • G01J1/02—Details
    • G01J1/04—Optical or mechanical part supplementary adjustable parts
    • G01J1/0488—Optical or mechanical part supplementary adjustable parts with spectral filtering
    • G01J1/0492—Optical or mechanical part supplementary adjustable parts with spectral filtering using at least two different filters
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J1/00—Photometry, e.g. photographic exposure meter
    • G01J1/42—Photometry, e.g. photographic exposure meter using electric radiation detectors
    • G01J1/4204—Photometry, e.g. photographic exposure meter using electric radiation detectors with determination of ambient light
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
    • G01J5/0022—Radiation pyrometry, e.g. infrared or optical thermometry for sensing the radiation of moving bodies
    • G01J5/0025—Living bodies
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
    • G01J5/02—Constructional details
    • G01J5/08—Optical arrangements
    • G01J5/0896—Optical arrangements using a light source, e.g. for illuminating a surface
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
    • G09G3/36—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source using liquid crystals
    • G09G3/3611—Control of matrices with row and column drivers
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
    • G01V8/00—Prospecting or detecting by optical means
    • G01V8/10—Detecting, e.g. by using light barriers
    • G01V8/20—Detecting, e.g. by using light barriers using multiple transmitters or receivers
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00—Control of display operating conditions
    • G09G2320/06—Adjustment of display parameters
    • G09G2320/0626—Adjustment of display parameters for control of overall brightness
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00—Control of display operating conditions
    • G09G2320/06—Adjustment of display parameters
    • G09G2320/0666—Adjustment of display parameters for control of colour parameters, e.g. colour temperature
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2330/00—Aspects of power supply; Aspects of display protection and defect management
    • G09G2330/02—Details of power systems and of start or stop of display operation
    • G09G2330/021—Power management, e.g. power saving
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2360/00—Aspects of the architecture of display systems
    • G09G2360/14—Detecting light within display terminals, e.g. using a single or a plurality of photosensors
    • G09G2360/144—Detecting light within display terminals, e.g. using a single or a plurality of photosensors the light being ambient light
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2360/00—Aspects of the architecture of display systems
    • G09G2360/14—Detecting light within display terminals, e.g. using a single or a plurality of photosensors
    • G09G2360/145—Detecting light within display terminals, e.g. using a single or a plurality of photosensors the light originating from the display screen
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
    • G09G3/3406—Control of illumination source
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G5/00—Control arrangements or circuits for visual indicators common to cathode-ray tube indicators and other visual indicators
    • G09G5/10—Intensity circuits
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03K—PULSE TECHNIQUE
    • H03K2217/00—Indexing scheme related to electronic switching or gating, i.e. not by contact-making or -breaking covered by H03K17/00
    • H03K2217/94—Indexing scheme related to electronic switching or gating, i.e. not by contact-making or -breaking covered by H03K17/00 characterised by the way in which the control signal is generated
    • H03K2217/941—Indexing scheme related to electronic switching or gating, i.e. not by contact-making or -breaking covered by H03K17/00 characterised by the way in which the control signal is generated using an optical detector
    • H03K2217/94102—Indexing scheme related to electronic switching or gating, i.e. not by contact-making or -breaking covered by H03K17/00 characterised by the way in which the control signal is generated using an optical detector characterised by the type of activation
    • H03K2217/94108—Indexing scheme related to electronic switching or gating, i.e. not by contact-making or -breaking covered by H03K17/00 characterised by the way in which the control signal is generated using an optical detector characterised by the type of activation making use of reflection

Definitions

  • the present invention relates to an optical sensor used for proximity detection and illuminance measurement.
  • Mobile terminals such as mobile phones and digital cameras use liquid crystal panels as information display devices.
  • a proximity sensor In such a portable terminal, by installing a proximity sensor, there is a demand for detecting a situation where a user brings a face close to the portable terminal, suppressing display on the liquid crystal panel, and reducing power consumption of the portable terminal. is increasing.
  • the above-described mobile terminal is equipped with an illuminance sensor to measure the illuminance of the environment where the liquid crystal panel is used, and to control the amount of light emitted from the backlight included in the liquid crystal panel according to the measurement result.
  • an illuminance sensor to measure the illuminance of the environment where the liquid crystal panel is used, and to control the amount of light emitted from the backlight included in the liquid crystal panel according to the measurement result.
  • FIG. 15 is a circuit diagram showing the main part of the optical sensor according to the prior art described in Patent Document 1.
  • the optical sensor described in Patent Document 1 includes two light receiving elements PD1 and PD2 having different spectral characteristics (spectral sensitivity characteristics) and a current mirror circuit, and receives light via the current mirror circuit.
  • a current ⁇ ⁇ Iin1 obtained by multiplying the amplitude of the photocurrent Iin1 generated by the element PD1 by ⁇ is obtained and subtracted from the photocurrent Iin2 generated by the light receiving element PD2 to obtain a current (Iin2- ⁇ ⁇ Iin1).
  • the spectral characteristic of the photosensor becomes a spectral characteristic that combines the spectral characteristics of the respective light receiving elements.
  • the light receiving element PD1 is disposed so as to be sandwiched between the light receiving elements PD2. Thereby, even when the amount of incident light to the light receiving element is not uniform, the bias of the photocurrent generated from the light receiving element is reduced.
  • FIG. 16 is a plan view showing a main part of a conventional optical sensor described in Patent Document 2.
  • the optical sensor described in Patent Document 2 includes two light receiving elements PD1 and PD2 that are equally distributed in a plane and have different spectral characteristics, and a photocurrent generated from the light receiving element PD1. Then, a current obtained by directly subtracting the photocurrent generated from the light receiving element PD2 is obtained. Thereby, the spectral characteristic of the photosensor becomes a spectral characteristic that combines the spectral characteristics of the respective light receiving elements.
  • the light receiving elements PD1 and PD2 are evenly arranged in a plane, and even if the angle of incident light to the light receiving element is biased, the photocurrent generated from the light receiving element is biased. Reduced.
  • Japanese Patent Publication Japanese Patent Laid-Open No. 2007-73591 (published March 22, 2007)” Japanese Patent Publication “JP 2009-182189 (released on August 13, 2009)”
  • the light sensor reflects the light emitted from the light emitting element to the object and receives the reflected light by the light receiving element, thereby detecting that the object is close.
  • Such an optical sensor may be used by being incorporated in a casing of a mobile terminal, for example.
  • the light emitted from the light emitting element may be reflected by the housing, and the light receiving element may receive the reflected light.
  • the possibility that the light receiving element receives such reflected light as a disturbance is not taken into consideration, and the optical sensor does not reflect the reflected light from the object whose proximity should be detected.
  • the optical sensor does not reflect the reflected light from the object whose proximity should be detected.
  • the reflected light from the body cannot be distinguished and the proximity of the object cannot be detected accurately.
  • the spectral characteristics and the arrangement position of the light receiving element are fixed. Therefore, when the amount of incident light to the light receiving element is not uniform, or the angle of the incident light to the light receiving element is If it is biased, the bias of the photocurrent generated from the light receiving element is not sufficiently reduced.
  • the light sensor is configured such that the light receiving elements PD1 and PD2 are uniformly included in a plane of incidence (lens spot) of the light, but the lens spot is shifted. In this case, the photocurrent generated from the light receiving element is biased.
  • the possibility that the light receiving element receives the light with the lens spot shifted as a disturbance is not sufficiently considered, and the optical sensor accurately determines the illuminance. There is a problem that it cannot be measured.
  • the present invention has been made in view of the above-described problems, and an object of the present invention is to provide an optical sensor capable of suppressing adverse effects caused by disturbance light in proximity detection and illuminance measurement.
  • an optical sensor includes a substrate and measures an amount of received light, and the photosensor is arranged on the substrate and receives photocurrent.
  • FIG. 1 is utilized for illumination intensity measurement. It is a graph which shows the spectral characteristic of the light receiving element when the optical sensor shown in FIG. 1 is utilized for illumination intensity measurement. It is a top view which shows the structure of the principal part of the optical sensor which concerns on other embodiment of this invention. It is a top view which shows the other structure of the principal part of the optical sensor shown in FIG. It is a figure which shows the structure of the modification of the analog-digital conversion part shown in FIG. 9 and FIG. It is a wave form diagram which shows the operation
  • FIG. 12 is a waveform diagram of a digital signal or the like output in proximity detection by the analog-digital conversion unit shown in FIGS.
  • FIG. 1 is a plan view showing a configuration of an optical sensor 1 according to an embodiment of the present invention.
  • the optical sensor 1 includes a light receiving element group PDG and a control unit 10.
  • the light receiving element group PDG includes 16 light receiving elements (PDs 11 to 14, 21 to 24, 31 to 34, 41 to 44) arranged on a substrate (described later in FIG. 4).
  • “light receiving element PD” means any one of the 16 light receiving elements.
  • the configuration is not limited to the configuration illustrated in FIG. 1, and the light receiving element group PDG only needs to include at least two, that is, a plurality of light receiving elements.
  • a region D represents a region on the substrate on which 16 light receiving elements are arranged.
  • the control unit 10 includes a light receiving element selecting unit (light receiving element selecting unit) 11, a spectral characteristic setting unit (spectral characteristic setting unit) 12, and a received light amount calculating unit (received light amount calculating unit) 13.
  • the light sensor measures the amount of light received based on the photocurrent generated from each light receiving element.
  • the directions of the X axis and the Y axis are directions representing a plane in which the region D is widened, and the direction of the Z axis is a normal direction of the light receiving surface of each light receiving element, which are shown in other drawings. Corresponds to the X to Z axis directions.
  • the light receiving element PD will be described in detail.
  • FIG. 2 is a cross-sectional view showing the configuration of the light receiving element PD of the optical sensor 1 shown in FIG.
  • the light receiving element PD has a configuration of P substrate (Psub) -N well (Nwell) -P diffusion (Pdif), and a PN junction between the P substrate (Psub) and the N well (Nwell).
  • the switching unit SWS includes a switch SWa and a switch SWb.
  • the switching unit SWS is connected to the spectral characteristic setting unit 12 (see FIG. 1), and the spectral characteristic setting unit 12 switches ON / OFF of each switch. Thereby, the spectral characteristic setting unit 12 sets the spectral characteristic of the light receiving element PD.
  • the “spectral characteristic of the light receiving element PD” means the relationship between the wavelength of light of a certain amount of light and the magnitude of the input current (photocurrent) Iin that the light receiving element PD receives and generates the light. Further, “setting the spectral characteristics of the light receiving element PD” means that the magnitude of the input current Iin that the light receiving element PD receives and generates light of a certain amount of light with respect to a wavelength included in a predetermined range. It means setting. Below, each element with which light receiving element PD is provided is demonstrated in detail.
  • the infrared light receiving PN junction PDir has infrared spectral characteristics. This is because infrared light included in the light incident on the light receiving element PD propagates to a deeper layer (negative direction of the Z axis) of the light receiving element PD as compared with visible light.
  • the “infrared spectral characteristics” means that the magnitude of the photocurrent generated by the infrared light receiving PN junction PDir receiving and generating a fixed amount of infrared light is the same as that of the infrared light receiving PN junction PDir.
  • the wavelength of the light received by the PN junction PDir for receiving infrared light which is larger than the magnitude of the photocurrent generated by receiving light of light quantity and not infrared light, and the magnitude of the generated photocurrent Means the relationship.
  • the visible light receiving PN junction PDvis has visible spectral characteristics. This is because visible light included in the light incident on the light receiving element PD does not propagate to the deep layer side of the light receiving element PD as much as infrared light.
  • the “visible spectral characteristic” means that the magnitude of the photocurrent generated by the visible light receiving PN junction PDvis receiving and generating a certain amount of visible light is the same as the visible light receiving PN junction PDvis. This means the relationship between the wavelength of light received by the visible light receiving PN junction PDvis and the magnitude of the photocurrent, which is larger than the magnitude of the photocurrent generated by receiving light that is not visible light.
  • the switching unit SWS uses the switch SWa and the switch SWb to switch the connection state between the infrared light receiving PN junction PDir and the visible light receiving PN junction PDvis.
  • the switch SWa is connected between the node N0 and the node N2.
  • the node N0 is connected to the cathode of the visible light receiving PN junction PDvis through the node N1.
  • the node N2 is connected to the anode of the visible light receiving PN junction PDvis. Therefore, when the switch SWa is turned on and the switch SWb is turned off, the potential of the cathode and the anode of the visible light receiving PN junction PDvis becomes the same, so that a photocurrent is generated from the visible light receiving PN junction PDvis. Only the photocurrent generated from the infrared light receiving PN junction PDir is output as the input current Iin to the node N0. Thereby, the spectral characteristics of the light receiving element PD can be changed to infrared spectral characteristics.
  • the “infrared spectral characteristics” means that the magnitude of the input current Iin that the light receiving element PD receives and generates a fixed amount of infrared light is that the light receiving element PD is the light of the constant light amount. This means the relationship between the wavelength of light received by the light receiving element PD and the magnitude of the input current Iin to be generated, which is larger than the magnitude of the input current Iin that is received and generated by the light.
  • the switch SWb is connected between the node N2 and the ground. Therefore, when the switch SWa is turned off and the switch SWb is turned on, a current obtained by adding the photocurrent generated from the visible light receiving PN junction PDvis and the photocurrent generated from the infrared light receiving PN junction PDir. Is output as the input current Iin to the node N0. As a result, the spectral characteristics of the light receiving element PD can be changed from visible to infrared.
  • the “visible to infrared spectral characteristics” means that the magnitude of the input current Iin that is generated when the light receiving element PD receives visible to infrared light with a constant light amount is that the light receiving element PD receives the light with the constant light amount. This means the relationship between the wavelength of light received by the light receiving element PD and the magnitude of the input current Iin to be generated, which is larger than the magnitude of the input current Iin that is received and generated by light that is not visible to infrared light. .
  • visible to infrared light means light included in visible light or infrared light.
  • the light receiving element selection unit 11 selects some of the light receiving elements among the plurality of light receiving elements included in the light receiving element group PDG. Note that the light receiving element selection unit 11 may select a plurality of light receiving elements.
  • the light receiving element selection unit 11 is connected to the received light amount calculation unit 13 and transmits information indicating which light receiving element is the selected light receiving element to the received light amount calculation unit 13.
  • the spectral characteristic setting unit 12 is connected to a switching unit SWS included in the light receiving element PD, and sets the spectral characteristics of 16 light receiving elements included in the light receiving element group PDG.
  • the spectral characteristic setting unit 12 may collectively set the spectral characteristics of a plurality of light receiving elements.
  • the spectral characteristic setting unit 12 is connected to the received light amount calculation unit 13 and transmits information indicating what spectral characteristic the spectral characteristic set in the light receiving element PD is to the received light amount calculation unit 13. .
  • the light receiving element selection unit 11 and the spectral characteristic setting unit 12 are connected to each other, and the spectral characteristic setting unit 12 determines what spectral characteristics are set for the light receiving element selected by the light receiving element selection unit 11. Information indicating whether the light has spectral characteristics is transmitted to the received light amount calculation unit 13.
  • the received light amount calculation unit 13 waits for a photocurrent generated from the light receiving element selected by the light receiving element selection unit 11 and whose spectral characteristics are set by the spectral characteristic setting unit 12, and receives the amount of light received by the optical sensor 1. Calculate
  • optical sensor 1 With the optical sensor 1 having the above-described configuration and the method of measuring the amount of received light using the optical sensor 1, adverse effects caused by light that becomes a disturbance can be suppressed in proximity detection and illuminance measurement.
  • operations when the optical sensor 1 is used for proximity detection and illuminance measurement will be described in order.
  • FIG. 3 is a plan view showing an operation when the optical sensor 1 shown in FIG. 1 is used for proximity detection.
  • the optical sensor 1 includes a light emitting element LED that emits at least infrared light, and an LED drive circuit DC that drives the light emitting element LED.
  • a light emitting diode may be used as the light emitting element LED.
  • the optical sensor 1 may include a plurality of light emitting elements LED.
  • the light receiving element selection unit 11 (see FIG. 1), among the 16 light receiving elements included in the light receiving element group PDG, a part of the light receiving elements (PD13) arranged in the region Da on the light emitting element side of the region D. , 14, 23, 24, 33, 34, 43, 44).
  • the spectral characteristic setting unit 12 (see FIG. 1) sets infrared spectral characteristics as the spectral characteristics of the light receiving element selected by the light receiving element selecting unit 11.
  • the optical sensor 1 is designed so that light enters the range indicated by the light spot S.
  • other light may further enter the range indicated by the light spot Sa due to the cause described later. That is, the light incident on the range indicated by the light spot Sa is light that causes disturbance, and can cause the optical sensor 1 to malfunction.
  • the optical sensor 1 can suppress an adverse effect caused by light that becomes a disturbance in proximity detection.
  • this principle will be described in detail.
  • FIG. 4 is a cross-sectional view showing an operation when the optical sensor 1 shown in FIG. 1 is used for proximity detection.
  • the optical sensor 1 reflects the light emitted from the light emitting element LED to the proximity detection object 41 and receives the reflected light by the light receiving element group PDG arranged on the substrate 21, thereby making the proximity It detects that the detection object 41 is approaching.
  • Such an optical sensor 1 may be used by being incorporated in, for example, a mobile panel housing 31 that is a housing of a mobile terminal. Note that “inside the mobile panel casing 31” means a space on the negative side of the Z axis with respect to the mobile panel casing 31 in FIG.
  • the optical sensor 1 is incorporated in the portable panel casing 31 with a distance d from the portable panel casing 31.
  • the case reflected light emitted from the light emitting element LED and reflected by the portable panel casing 31 enters the light receiving element group PDG, and the light receiving element group PDG is emitted from the light emitting element LED and is a proximity detection object outside the casing.
  • a photocurrent similar to the photocurrent generated when the object reflected light reflected by 41 is incident on the light receiving element may be generated.
  • the conventional optical sensor cannot distinguish between the case reflected light and the object reflected light, and erroneously detects that the proximity detection object 41 is close even if it is not close to the optical sensor.
  • FIG. 5 is a cross-sectional view showing another operation when the optical sensor 1 shown in FIG. 1 is used for proximity detection.
  • the distance da between the optical sensor 1 and the portable panel housing 31 is larger than the distance d shown in FIG. Narrow.
  • the angle ⁇ a formed by the case reflected light with the portable panel case 31 is smaller than the angle ⁇ shown in FIG.
  • the case reflected light shown in FIG. 5 enters the light receiving element group PDG, the case reflected light is further away from the light emitting element LED side in the negative direction of the X axis than the case reflected light shown in FIG. Incident.
  • the optical sensor tends to be used by being incorporated in a smaller portable terminal, the reflected light from the casing may be incident on a position further away from the light emitting element LED side in the negative direction of the X axis. high.
  • the light receiving element selection unit 11 is a part of the 16 light receiving elements included in the light receiving element group PDG that is arranged in the area Da on the light emitting element LED side of the area D.
  • the received light amount calculation unit 13 In order to select the light receiving element (see FIG. 3), that is, the light receiving element that is less likely to receive the case reflected light than other light receiving elements, the received light amount calculation unit 13 (see FIG. 1) In this calculation, the influence of the case reflected light can be suppressed. In other words, the optical sensor 1 adjusts the optical characteristics so as to positively receive object reflected light by selecting some of the 16 light receiving elements arranged in the region D. In addition, it is possible to reduce the received light amount of the case reflected light that becomes noise in the measurement of the received light amount.
  • FIG. 6 is a cross-sectional view showing an operation when the optical sensor 101 according to the comparative example of the optical sensor 1 shown in FIG. 1 is used for proximity detection.
  • the optical sensor 101 is different from the optical sensor 1 in that it includes a shielding object 102.
  • the shield 102 prevents the case reflected light from entering the light receiving element group PDG.
  • the photosensor 1 may not be provided with the shield 102.
  • the configuration according to the comparative example cannot often be employed.
  • the increased cost of incorporating the shielding object 102 into the optical sensor cannot be allowed.
  • the optical sensor 1 may be used in an environment where, for example, visible light emitted from a fluorescent lamp enters the light receiving element PD.
  • the spectral characteristic setting unit 12 sets the infrared spectral characteristic as the spectral characteristic of the light receiving element selected by the light receiving element selection unit 11 (see FIG. 1).
  • the light receiving element suppresses generation of a photocurrent caused by visible light, and selectively receives infrared light emitted from the light emitting element LED (see FIG. 3) to generate a photocurrent. Therefore, the received light amount calculation unit 13 (see FIG. 1) can suppress the influence of visible light in the calculation of the received light amount.
  • the optical sensor 1 is suitable for proximity detection because it can suppress erroneous detection due to visible light.
  • the optical sensor can suppress adverse effects caused by the reflected light from the housing and is suitable for proximity detection.
  • FIG. 7 is a plan view showing an operation when the optical sensor 1 shown in FIG. 1 is used for illuminance measurement.
  • the light receiving element selection unit 11 receives the light received in a part of the region Db near the center of the region D among the 16 light receiving elements included in the light receiving element group PDG.
  • the element (PD22, 23, 32, 33) is selected.
  • the spectral characteristic setting unit 12 selects either the visible to infrared spectral characteristic or the infrared spectral characteristic as the spectral characteristic of the light receiving element selected by the light receiving element selecting unit 11. To do.
  • the received light amount calculation unit 13 see FIG.
  • the spectral characteristic setting unit 12 sets the visible to infrared spectral characteristic. While the infrared spectral characteristic is set by the unit 12, the magnitude of the photocurrent generated from the light receiving element is subtracted to calculate the amount of received light.
  • the optical sensor 1 is designed so that light enters the range indicated by the light spot S.
  • the light may be incident on the range indicated by the light spot Sb. That is, part of the light incident on the range indicated by the light spot Sb is a disturbance light and may cause the optical sensor 1 to malfunction.
  • the optical sensor 1 can suppress an adverse effect caused by the disturbing light in the illuminance measurement.
  • this principle will be described in detail.
  • the optical sensor 1 Normally, the center of gravity (incident center) of the intensity distribution of light (environmental light) incident from the outside of the optical sensor and the center of the light receiving area (light receiving center) into the area where the plurality of light receiving elements are arranged (light receiving area)
  • the optical sensor is designed to match.
  • the optical sensor 1 is designed so that light enters the range indicated by the light spot S shown in FIG.
  • each center may be shifted due to external force acting on the optical sensor or aging deterioration. For this reason, the optical sensor according to the related art may not be able to measure the illuminance of the environment where the optical sensor is placed as designed.
  • the incident center is expected to shift to a position moved in a random direction from the light receiving center, the expected incident center coincides with the light receiving center.
  • the light spot Sb is a part of the vicinity of the center of the region D even when the light is incident on the light spot Sb instead of the light spot S. It is expected to include a partial region Db.
  • the light receiving element selection unit 11 receives a part of the light received in the region Db near the center of the region D among the 16 light receiving elements included in the light receiving element group PDG.
  • the received light amount calculation unit 13 By selecting an element, that is, a light receiving element that is more likely to receive ambient light than other light receiving elements, the received light amount calculation unit 13 (see FIG. 1) The influence of deviation can be suppressed.
  • the optical sensor 1 adjusts the optical characteristics so as to actively receive ambient light by selecting some of the 16 light receiving elements arranged in the region D.
  • FIG. 8 is a graph showing the spectral characteristics of the light receiving element PD when the optical sensor 1 shown in FIG. 1 is used for illuminance measurement.
  • the horizontal axis indicates the wavelength of light incident on the light receiving element PD
  • the vertical axis indicates the amount of light in watts (W) and the photocurrent generated from the light receiving element PD in amperes (A). The ratio of both is shown.
  • W watts
  • A amperes
  • the ratio of both is shown.
  • the infrared spectral characteristic is subtracted by ⁇ times from the visible to infrared spectral characteristic, the spectral characteristic close to the visibility is obtained.
  • the value of ⁇ is selected so as to match the known visibility.
  • “Visibility” means the degree of brightness perceived by a person when the human eye receives light of the wavelength with respect to a wavelength included in a predetermined range.
  • the visual sensitivity takes a maximum value for the wavelength near the center of the visible light wavelength range (about 400 to 700 nm), and takes a smaller value for wavelengths closer to both ends of the range.
  • spectral characteristics close to visual sensitivity means that the spectral characteristics are close to the relationship between the wavelength of light received by the human eye and the degree of brightness that the person perceives visually.
  • the spectral characteristic setting unit 12 sets the visible to infrared spectral characteristic as the spectral characteristic of the light receiving element PD, the light receiving element is visible to infrared. A photocurrent corresponding to the amount of received light is generated. Further, while the spectral characteristic setting unit 12 sets the infrared spectral characteristic as the spectral characteristic of the light receiving element, the light receiving element generates a photocurrent corresponding to the amount of received infrared light.
  • the received light amount calculation unit 13 subtracts the magnitude of the photocurrent according to the amount of received light of infrared light from the magnitude of the photocurrent according to the amount of received light of visible to infrared light.
  • the magnitude of the photocurrent according to the amount of received visible light can be calculated.
  • the optical sensor 1 is suitable for illuminance measurement because it can realize spectral characteristics close to the visibility.
  • the optical sensor 1 can suppress an adverse effect caused by a shift in the incident center of ambient light and is suitable for illuminance measurement.
  • the optical sensor 1 is not limited to the configuration shown in FIG. 2, and the light receiving element PD may include three or more PN junctions having different spectral characteristics. In other words, the light receiving element PD may further include a PN junction other than the infrared light receiving PN junction PDir and the visible light receiving PN junction PDvis.
  • the switching unit SWS may switch the connection state between the PN junctions using three or more switches.
  • three or more PN junctions generate photocurrents corresponding to the amounts of three or more types of light that are included in the light received by the light receiving element PD and have different wavelengths.
  • the received light amount calculation unit 13 can receive a photocurrent corresponding to the amount of light of three or more types from the light receiving element PD.
  • the optical sensor 1 can suppress adverse effects caused by various kinds of light as disturbances in proximity detection and illuminance measurement.
  • the optical sensor 1 further includes a resin sealing portion 22 that seals the light receiving element group PDG.
  • the resin sealing portion 22 is located in a region on the substrate 21 where the light receiving element group PDG is disposed. You may have the lens (lens shape) 23 which condenses light.
  • the lens receives light received by the light sensor in a narrow area.
  • the lens allows the optical sensor to have high directivity with respect to the optical axis direction of the lens.
  • the focal point of the lens is matched with the area. In such a case, it is preferable that the relative positional relationship between the lens and the region where the light is collected is fixed.
  • the light received by the optical sensor 1 is condensed on the light receiving area by the lens 23 and the relative positional relationship between the lens 23 and the light receiving area is fixed, so that the light receiving area is narrowed. Even in this case, the light receiving element PD can accurately receive light.
  • FIG. 9 is a plan view showing a configuration of a main part of an optical sensor 1 according to another embodiment of the present invention.
  • the optical sensor 1 includes an analog-to-digital conversion unit (analog-to-digital conversion means) ADC that converts the magnitude of the photocurrent Ia generated from the light receiving element PD included in the region Da into a digital value ADCOUTa.
  • ADC analog-to-digital conversion unit
  • the controller 10a may be configured by adding an analog-digital converter ADC to the controller 10 (see FIG. 1).
  • the other structure of the optical sensor 1 is the same as that of the optical sensor 1 utilized for the proximity detection shown in FIG.
  • the analog-digital conversion unit ADC can convert the magnitude of the photocurrent Ia corresponding to the amount of light received by each light receiving element PD into a digital value ADCOUTa. That is, the optical sensor 1 can output a digital value representing the amount of received light that can be subjected to desired digital processing in proximity detection.
  • the photocurrent Ia is a photocurrent generated from the light receiving element PD while the infrared spectral characteristic is set by the spectral characteristic setting unit 12.
  • FIG. 10 is a plan view showing another configuration of the main part of the optical sensor 1 shown in FIG.
  • the optical sensor 1 further includes a plurality of analog-digital conversion units (analog-digital conversion means) ADCs that convert the magnitudes of the photocurrents Ib and Ic generated from the light receiving element PD into digital values. May be.
  • a controller 10b is configured by adding two analog-to-digital converters ADC to the controller 10 (see FIG. 1), and the received light amount calculator 13 (see FIG. 1) has a first analog signal.
  • the subtraction between the digital value ADCOUTb output from the digital conversion unit ADC and the digital value ⁇ ⁇ ADCOUTc obtained by multiplying the digital value ADCOUTc output from the second analog-digital conversion unit ADC by ⁇ by a multiplier (not shown) is performed. It may be.
  • the other structure of the optical sensor 1 is the same as that of the optical sensor 1 utilized for the illumination intensity measurement shown in FIG.
  • the magnitudes of the photocurrents Ib and Ic corresponding to the amount of light received by each light receiving element PD can be converted into digital values (ADCOUTb- ⁇ ⁇ ADCOUTc) by the analog-digital conversion unit ADC. That is, the optical sensor 1 can output a digital value representing the amount of received light that can be subjected to desired digital processing in illuminance measurement.
  • the photocurrent Ib is a photocurrent generated from the light receiving element PD while the visible to infrared spectral characteristics are set by the spectral characteristic setting unit 12, and the photocurrent Ic is red by the spectral characteristic setting unit 12. This is a photocurrent generated from the light receiving element PD while the external spectral characteristic is set.
  • FIG. 11 is a diagram illustrating a configuration according to a modification of the analog-digital conversion unit ADC illustrated in FIGS. 9 and 10.
  • the analog-digital conversion unit ADC includes a charging circuit (integrating circuit) 15, a discharging circuit 16, a comparison circuit 17, and a control circuit (output circuit) 18.
  • a charging circuit integrating circuit
  • a discharging circuit a comparison circuit
  • a control circuit output circuit
  • the charging circuit 15 includes an amplifier AMP1 constituting an integrator and a capacitor (integrating capacitor) C1. An amount of electric charge corresponding to the input current Iin is stored in the capacitor C1.
  • the discharge circuit 16 includes a power supply Vdd, a reference current source Iref that generates a reference current IREF for discharging the charge stored in the capacitor C1, and a switch SW2 for switching ON / OFF of discharge.
  • the comparison circuit 17 includes a comparator CMP1 and a switch SW1.
  • the comparator CMP1 compares the output voltage Vsig of the charging circuit 15 with the reference voltage Vref supplied by the reference voltage source V1, and outputs an output signal (pulse signal) comp.
  • the data conversion period in which the input current Iin is converted to the digital value ADCOUT is determined by turning on / off the switch SW1.
  • the switch SW1 when the switch SW1 is turned on, the reference voltage source V1 is connected to the charging circuit 15, the reference voltage Vref is supplied to the capacitor C1, and the capacitor C1 is charged.
  • the comparator CMP1 When the switch SW1 is turned off, the output voltage Vsig of the charging circuit 15 and the reference voltage Vref are compared by the comparator CMP1.
  • the comparison output signal comp is input to the control circuit as a binary pulse signal of “High” and “Low”.
  • An input current Iin that is input while the switch SW1 is OFF is converted to a digital value ADCOUT.
  • the control circuit 18 includes a flip-flop FF and a counter COUNT.
  • the output signal comp of the comparison circuit 17 is latched by the flip-flop FF.
  • the bit stream signal charge is input to the discharge circuit 16 and the counter COUNT, respectively.
  • the counter COUNT counts the number of LOW levels (the number of discharges) of the bit stream signal charge. That is, the counter COUNT counts active pulses. Further, the count result is output as a digital value ADCOUT which is an analog-digital conversion value corresponding to the input current Iin.
  • the switch SW2 of the discharge circuit 16 is turned ON / OFF based on the bit stream signal charge.
  • the switch SW2 of the discharge circuit 16 is turned on, electric charge is stored in the capacitor C1 of the charging circuit 15 by the discharge circuit 16.
  • the switch SW2 is turned off, the charge of the capacitor C1 of the charging circuit 15 is discharged according to the input current Iin.
  • FIG. 12 is a waveform diagram showing an operation of the analog-digital conversion unit ADC shown in FIG.
  • the switch SW2 when a high level signal is input to the switch SW2, the switch SW2 is turned off, and the charge stored in the capacitor C1 of the charging circuit 15 is discharged according to the input current Iin (precharge operation). As a result, the output voltage Vsig of the charging circuit 15 decreases.
  • the output voltage Vsig of the charging circuit 15 and the reference voltage Vref are set in the same manner, the output voltage Vsig of the charging circuit falls below the reference voltage Vref during this period.
  • the switch SW2 When a low level signal is input to the switch SW2, the switch SW2 is turned on, and the capacitor C1 of the charging circuit 15 is charged by the discharging circuit 16 with the electric charge. As a result, the output voltage Vsig of the charging circuit 15 increases. At some point, the output voltage Vsig of the charging circuit 15 exceeds the reference voltage Vref.
  • the output voltage Vsig of the charging circuit 15 and the reference voltage Vref are compared by the comparator CMP1, and when the output voltage Vsig of the charging circuit 15 exceeds the reference voltage Vref, a high level output signal comp is output from the comparator CMP1. .
  • the flip-flop FF latches the output signal comp, and in synchronization with the rise of the next clock signal clk, the high-level bit stream signal charge. Is output.
  • the switch SW2 When the high-level bit stream signal charge is input to the switch SW2, the switch SW2 is turned off, and the charge stored in the capacitor C1 of the charging circuit 15 is discharged. As a result, the output voltage Vsig of the charging circuit 15 decreases. At some point, the output voltage Vsig of the charging circuit 15 falls below the reference voltage Vref. When the output voltage Vsig of the charging circuit 15 falls below the reference voltage Vref, a low level output signal comp is output as an active pulse indicating that the output of the comparator CMP1 is at the active level. Note that the active pulse may be set to either the Low level or the High level, and can be appropriately selected depending on the operation logic of the circuit.
  • the flip-flop FF latches the output signal comp so that the control circuit 18 takes in the output signal comp, and the flip-flop FF A low-level bit stream signal charge is output in synchronization with the rise of the signal clk.
  • the switch SW2 When a low-level bit stream signal charge is input to the switch SW2, the switch SW2 is turned on.
  • the bit stream signal charge is a time-series arrangement of low level signals (active pulses), and the switch SW2 is turned on during the low level period (active pulse period).
  • the analog-digital conversion unit ADC repeats the above operation, and the counter COUNT counts the number of discharges count of the discharge circuit 16 during the period in which the switch SW1 is turned off, that is, the data conversion period t_conv. It becomes possible to output a digital value ADCOUT corresponding to the current Iin.
  • the amount of charge charged by the input current Iin in the data conversion period t_conv is, assuming that the period of the clock signal clk is t_clk.
  • the minimum resolution of the analog-digital conversion unit ADC is determined by (IREF ⁇ t_clk).
  • the integration type analog-to-digital conversion unit ADC can perform analog-to-digital conversion with a wide dynamic range and high resolution. Further, such an integral type analog-digital conversion unit ADC is suitable for an illuminance sensor or a proximity sensor.
  • the analog-to-digital conversion unit ADC uses the current output from each of the above-described sensors as the input current Iin and performs analog-to-digital conversion and uses a digital value, thereby providing a highly accurate color temperature with an inexpensive configuration.
  • the illuminance can be calculated.
  • the input voltage to the non-inverting input terminal of the amplifier AMP1 can be set to 0V.
  • the both-ends voltage (bias voltage) of the above-mentioned PN junction (PDir, PDvis) can be set to 0V. Therefore, it is possible to reduce the dark current of the PN junction, and it is possible to accurately measure even a low light amount. That is, measurement with low sensitivity can be performed accurately.
  • the optical sensor 1 can output a digital value representing the amount of received light that can be subjected to desired digital processing. Further, the optical sensor 1 can accurately measure the amount of received light with low sensitivity.
  • FIG. 13 is a waveform diagram of digital signals and the like output in proximity detection by the analog-to-digital conversion unit ADC shown in FIGS. 9 to 11, and (a) shows a case where the proximity of an object is detected, and (b) FIG. 5 is a diagram illustrating a case where non-adjacent objects are detected.
  • the configuration of the optical sensor 1 is the same as the configuration shown in FIG. Here, if the digital signal DOUT during the period when the light emitting element LED is driven is Data1, and the digital signal DOUT during the period when the light emitting element LED is not driven is Data2, the difference between the data (Data1-Data2) is close. It becomes data.
  • the proximity data (Data 1 -Data 2) exceeds the threshold Data_th of the control circuit, and thus is determined to be close.
  • the proximity data (Data 1 -Data 2) does not exceed the threshold Data_th of the control circuit, and is thus determined as non-proximity.
  • FIG. 14 is a block diagram showing a schematic configuration of a display device 5 according to another embodiment of the present invention.
  • the display device 5 includes the optical sensor 1, a backlight control unit 51, a backlight 52, and a liquid crystal panel 55.
  • the backlight 52 is a light source for irradiating light from the back surface of the liquid crystal panel 55 that displays a screen, and has, for example, a red LED, a green LED, and a blue LED.
  • the optical sensor 1 receives the ambient light of the display device 5 and measures the color component of the ambient light, and outputs a digital signal DOUT to the backlight control unit 51 as a measurement result.
  • the backlight control unit 51 calculates a color component and illuminance by calculating from the digital signal DOUT. Based on the calculated information, the brightness of the red LED, green LED, and blue LED of the backlight 52 is controlled to control the color of the backlight 52 according to the color component of the ambient light or The brightness can be controlled.
  • the backlight control unit 51 controls to increase the luminance of the backlight 52, and when the illuminance of the ambient light is small, the backlight control unit 51 decreases the luminance of the backlight 52. To control. Thereby, the power consumption of the backlight 52 can be suppressed, and the color of the liquid crystal panel 55 can be accurately controlled so as to correspond to the color adaptation of the eyes.
  • the display device 5 can accurately detect the proximity of the surrounding object by the optical sensor 1, the brightness of the backlight 52 can be controlled according to the proximity of the surrounding object.
  • a display device 5 is suitable for a mobile phone or a digital still camera including a display panel such as the liquid crystal panel 55, for example.
  • the signal output from the optical sensor 1 may be converted by the above-described analog-digital conversion unit ADC.
  • the backlight control unit 51 performs the backlight based on the converted output signal.
  • the brightness of the light 52 may be controlled.
  • the display device 5 may be applied to other products and used as a part of an application product (mobile phone, digital camera) 6.
  • the control block (especially the control units 10, 10a, 10b) of the optical sensor 1 may be realized by a logic circuit (hardware) formed in an integrated circuit (IC chip) or the like, or a CPU (Central Processing Unit). And may be realized by software.
  • control units 10, 10 a, and 10 b include a CPU that executes instructions of a program that is software that realizes each function, and a ROM (Read that records the above program and various data so that the computer (or CPU) can read them. Only Memory) or a storage device (these are referred to as “recording media”), RAM (Random Access Memory) for expanding the program, and the like. And the objective of this invention is achieved when a computer (or CPU) reads the said program from the said recording medium and runs it.
  • a “non-temporary tangible medium” such as a tape, a disk, a card, a semiconductor memory, a programmable logic circuit, or the like can be used.
  • the program may be supplied to the computer via an arbitrary transmission medium (such as a communication network or a broadcast wave) that can transmit the program.
  • a transmission medium such as a communication network or a broadcast wave
  • the present invention can also be realized in the form of a data signal embedded in a carrier wave in which the program is embodied by electronic transmission.
  • the optical sensor 1 is an optical sensor that has a substrate 21 and measures the amount of received light, and is a plurality of light receiving elements (on the substrate) that receive light and generate a photocurrent.
  • Light receiving element group PDG Light receiving element group PDG
  • light receiving element selecting means light receiving element selecting unit 11
  • spectral characteristics for setting the spectral characteristics of the plurality of light receiving elements, respectively.
  • the photocurrent generated from the light receiving element selected by the setting means (spectral characteristic setting unit 12) and the light receiving element selecting means and having the spectral characteristic set by the spectral characteristic setting means is waited, and the amount of received light is calculated.
  • a received light amount calculation means (received light amount calculator 13).
  • the method for measuring the amount of received light includes the substrate 21 and a plurality of light receiving elements (light receiving element group PDG) arranged on the substrate to receive light and generate a photocurrent.
  • a light receiving element arranged at a specific position on the substrate is selected by the light receiving element selecting unit, and light having a specific wavelength is received by the spectral characteristic setting unit.
  • the spectral characteristic of the light receiving element is set so that a larger photocurrent is generated than when light of other wavelengths is received.
  • the received light amount calculation means can receive a photocurrent corresponding to the light amount of light having a specific wavelength, which is light incident on a specific position on the substrate, from the light receiving element.
  • the received light amount calculation means can calculate the received light amount of the photosensor while suppressing the adverse effect of the light incident on the position that causes the disturbance or the light having the wavelength that causes the disturbance.
  • such an optical sensor can be used for proximity detection for detecting an object close to the optical sensor and for illuminance measurement for measuring the illuminance of the environment where the optical sensor is placed.
  • the “spectral characteristic of the light receiving element” means the relationship between the wavelength of light having a certain amount of light and the magnitude of the photocurrent generated by the light receiving element receiving the light.
  • “Setting the spectral characteristics of the light receiving element” means setting the magnitude of the photocurrent that the light receiving element receives and generates a certain amount of light with respect to a wavelength included in a predetermined range. Means.
  • the optical sensor 1 according to aspect 2 of the present invention further includes a light emitting element LED that emits at least infrared light in the above aspect 1, and the light receiving element selection unit includes the light receiving element on the substrate among the plurality of light receiving elements. Select a part of the light receiving elements (PD13, 14, 23, 24, 33, 34, 43, 44) arranged on the light emitting element side of the region D where the plurality of light receiving elements are arranged, and set the spectral characteristics
  • the means may set an infrared spectral characteristic as the spectral characteristic of the light receiving element selected by the light receiving element selecting means.
  • the light sensor reflects the light emitted from the light emitting element to the object and receives the reflected light by the light receiving element, thereby detecting that the object is close.
  • Such an optical sensor may be used by being incorporated in a housing such as a portable terminal.
  • the case reflected light emitted from the light emitting element and reflected by the casing enters the light receiving element, and the light receiving element receives the object reflected light emitted from the light emitting element and reflected by an object outside the casing.
  • a photocurrent similar to the photocurrent generated when the light enters the light source is generated.
  • the optical sensor cannot distinguish between the case reflected light and the object reflected light, and erroneously detects that the object is close even if it is not close to the optical sensor.
  • the light receiving element selection unit includes a part of the plurality of light receiving elements disposed on the light emitting element side of the region where the plurality of light receiving elements are disposed on the substrate, that is, another light receiving element Therefore, the light receiving amount calculation unit can suppress the influence of the case reflected light in the calculation of the amount of received light.
  • the optical sensor adjusts the optical characteristics so as to positively receive object reflected light by selecting some of the light receiving elements arranged in the light receiving region, It is possible to reduce the received light amount of the case reflected light that becomes noise in the measurement of the received light amount.
  • the spectral characteristic setting unit sets the infrared spectral characteristic as the spectral characteristic of the light receiving element selected by the light receiving element selecting unit. Therefore, the light receiving element suppresses generation of a photocurrent caused by visible light, and selectively receives infrared light emitted from the light emitting element to generate a photocurrent. Therefore, the received light amount calculation means can suppress the influence of visible light in calculating the received light amount. In this way, the optical sensor is suitable for proximity detection because it can suppress erroneous detection due to visible light.
  • the optical sensor can suppress adverse effects caused by the reflected light from the housing and is suitable for proximity detection.
  • the “infrared spectral characteristics” means that the magnitude of the photocurrent generated when the light receiving element receives a fixed amount of infrared light is light that the light receiving element is not the infrared light.
  • the light receiving element selection unit is configured such that, among the plurality of light receiving elements, the region D in which the plurality of light receiving elements on the substrate are arranged. A part of the light receiving elements (PD22, 23, 32, 33) arranged in the vicinity of the center is selected, and the spectral characteristic setting means has visible to red as the spectral characteristics of the light receiving elements selected by the light receiving element selecting means. Either the spectral characteristic of the outside or the spectral characteristic of infrared is selected, and the received light amount calculating means is configured to receive from the light receiving element while the visible to infrared spectral characteristics are set by the spectral characteristic setting means. Calculate the amount of received light by subtracting the magnitude of the photocurrent generated from the light receiving element while the infrared spectral characteristics are set by the spectral characteristic setting means from the magnitude of the generated photocurrent. Also good.
  • the optical sensor is designed to match.
  • each center may be shifted due to external force acting on the optical sensor or aging deterioration. For this reason, the optical sensor may not be able to measure the illuminance of the environment where the optical sensor is placed as designed.
  • the incident center is expected to shift to a position moved in a random direction from the light receiving center, the expected incident center coincides with the light receiving center.
  • the received light amount calculation means can suppress the influence of the deviation of the incident center in the calculation of the received light amount.
  • the optical sensor adjusts the optical characteristics so as to actively receive ambient light by selecting some of the light receiving elements arranged in the light receiving region, and receives the light. It is possible to reduce variation in sensitivity representing the amount of received light that is actually output as a measurement result by the optical sensor with respect to the amount of received light.
  • the spectral characteristic setting unit sets the visible to infrared spectral characteristic as the spectral characteristic of the light receiving element
  • the light receiving element generates a photocurrent corresponding to the amount of received visible to infrared light.
  • the spectral characteristic setting means sets the infrared spectral characteristic as the spectral characteristic of the light receiving element
  • the light receiving element generates a photocurrent corresponding to the amount of received infrared light.
  • the received light amount calculation means subtracts the magnitude of the photocurrent according to the amount of received infrared light from the magnitude of the photocurrent according to the amount of received visible to infrared light, thereby receiving visible light.
  • the magnitude of the photocurrent according to the quantity can be calculated.
  • the optical sensor is suitable for illuminance measurement because it can realize spectral characteristics close to the visibility.
  • the optical sensor can suppress adverse effects caused by the deviation of the incident center of the ambient light and is suitable for illuminance measurement.
  • visible to infrared spectral characteristics means that the magnitude of the photocurrent generated when the light receiving element receives visible to infrared light with a certain amount of light is visible when the light receiving element is the light with the certain amount of light. It means the relationship between the wavelength of light received by the light receiving element and the magnitude of the photocurrent to be generated, which is larger than the magnitude of the photocurrent that is received and generated by light that is not infrared light.
  • visible to infrared light means light included in visible light or infrared light.
  • “Visibility” means the degree of brightness that a person's eyes perceive when light of the wavelength is received by a person's eyes with respect to wavelengths within a predetermined range.
  • the visual sensitivity takes a maximum value for the wavelength near the center of the visible light wavelength range (about 400 to 700 nm), and takes a smaller value for wavelengths closer to both ends of the range.
  • spectral characteristics close to visual sensitivity means that the spectral characteristics are close to the relationship between the wavelength of light received by the human eye and the degree of brightness that the person perceives visually.
  • each light receiving element may include an infrared light receiving PN junction PDir having infrared spectral characteristics. .
  • the received light amount calculating means A photocurrent corresponding to the amount of light can be received from the light receiving element.
  • the optical sensor can suppress adverse effects caused by infrared light that becomes a disturbance in proximity detection and illuminance measurement.
  • each light receiving element may include a visible light receiving PN junction PDvis having visible spectral characteristics.
  • the PN junction for receiving visible light generates a photocurrent corresponding to the amount of visible light contained in the light received by the light receiving element, so that the received light amount calculation means corresponds to the amount of visible light.
  • the received photocurrent can be received from the light receiving element.
  • the optical sensor can suppress an adverse effect caused by visible light that is a disturbance in proximity detection and illuminance measurement.
  • “Visible spectral characteristics” refers to the magnitude of the photocurrent generated when a light receiving element receives a certain amount of visible light, and the light receiving element receives light that is a certain amount of light but not visible light. It means the relationship between the wavelength of light received by the light receiving element and the magnitude of the photocurrent, which is larger than the magnitude of the photocurrent to be generated.
  • each light receiving element may include three or more PN junctions having different spectral characteristics.
  • the three or more PN junctions generate light currents corresponding to the light amounts of three or more types of light that are included in the light received by the light receiving element and have different wavelengths.
  • the received light amount calculation means can receive a photocurrent corresponding to the amount of light of three or more types from the light receiving element.
  • the optical sensor can suppress adverse effects caused by various kinds of light as disturbances in proximity detection and illuminance measurement.
  • the optical sensor 1 according to Aspect 7 of the present invention further includes a resin sealing portion 22 that seals the plurality of light receiving elements in any one of the Aspects 1 to 6, and the resin sealing portion includes the above-described resin sealing portion.
  • the light received by the light sensor is condensed in a narrow area by a lens or the like.
  • the focal point of the lens is matched with the area. In such a case, it is preferable that the relative positional relationship between the lens and the region where the light is collected is fixed.
  • the light received by the optical sensor is focused on the light receiving region by the lens shape, and the relative positional relationship between the lens shape and the light receiving region is fixed, so the light receiving region is narrowed. Even in this case, the light receiving element can accurately receive light.
  • the optical sensor 1 according to aspect 8 of the present invention is the optical sensor 1 according to any one of the aspects 1 to 7, wherein analog-digital conversion means (analog-digital conversion unit ADC) for converting the magnitude of the photocurrent into a digital value is provided. Furthermore, you may provide.
  • analog-digital conversion means analog-digital conversion unit ADC
  • the magnitude of the photocurrent corresponding to the amount of light received by the light receiving element can be converted into a digital value by the analog-digital conversion means. That is, the optical sensor can output a digital value representing the amount of received light that can be subjected to desired digital processing.
  • the optical sensor 1 according to Aspect 9 of the present invention includes, in any one of the Aspects 1 to 7, an integration capacitor (capacitor C1) that stores charges according to the magnitude of the photocurrent, and the integration capacitor stores the integration capacitor.
  • An integration circuit (charging circuit 15) that outputs a voltage corresponding to the amount of charge and the output voltage Vsig of the integration circuit and the reference voltage Vref are compared with each other, and the comparison result is expressed as a binary pulse signal (output).
  • a comparator circuit 17 that outputs the signal as a signal comp
  • a flip-flop FF that takes the pulse signal in synchronization with the clock signal clk and outputs the bit stream signal charge
  • a counter COUNT that counts the active pulses of the bit stream signal.
  • an output circuit (control circuit 18) for outputting a count result by the counter as a digital value.
  • the total length of the active pulse period corresponds to the magnitude of the photocurrent.
  • the output pulse current of the output circuit is integrated (that is, averaged) by the integration circuit, so that a digital value indicating the magnitude of the photocurrent is obtained.
  • the photosensor can convert the magnitude of the photocurrent corresponding to the amount of light received by the light receiving element into a digital value.
  • the optical sensor can output a digital value representing the amount of received light that can be processed in a desired manner.
  • the integration circuit can set the input voltage to the non-inverting input terminal of the amplifier to 0 V when outputting a voltage corresponding to the amount of charge stored in the integration capacitor using the amplifier.
  • the bias voltage of the light receiving element becomes 0V, and the light receiving element can reduce the dark current compared to the case where the bias voltage is not 0V. That is, the optical sensor can accurately measure the received light amount even when the received light amount is low and the photocurrent generated from the light receiving element is small. In other words, the optical sensor can accurately measure the amount of received light with low sensitivity.
  • the optical sensor 1 is the light sensor 1 according to any one of the aspects 1 to 9 generated from the two light emitting elements arranged at different positions on the substrate and the plurality of light receiving elements.
  • the center of gravity calculating means for calculating the center of gravity of the intensity distribution of the light incident on the region where the plurality of light receiving elements are arranged on the substrate, and while the first light emitting element emits light
  • a comparing means for comparing a distance between the center of gravity calculated by the center of gravity calculating means and the center of gravity calculated by the center of gravity calculating means while the second light emitting element emits light with a predetermined threshold;
  • a signal output means for outputting a signal indicating that the amount of received light measured by the optical sensor may not be a correct value when the distance exceeds the threshold value in the comparison result of the comparison means; May be.
  • the light emitted from the two light emitting elements may be reflected by the housing and enter the light receiving region.
  • each case reflected light is incident on different areas of the light receiving area.
  • the center-of-gravity calculating unit calculates the incident center of each case reflected light, and the comparing unit compares the distance between the incident centers (distance between incident centers) with a predetermined threshold.
  • the optical sensor determines whether the case reflected light is incident on the light receiving area. Can be notified.
  • the optical sensor can notify the outside whether or not the measured amount of received light is a correct value.
  • the optical sensor since the optical sensor includes at least two light emitting elements, measurement of the amount of received light can be continued using another light emitting element even if one light emitting element is broken.
  • the number of light-emitting elements included in the optical sensor is not limited to two, and may be three or more.
  • a display device includes a liquid crystal panel 55 that displays a screen, a backlight 52 that irradiates light to the liquid crystal panel, a backlight control unit 51 that controls the luminance of the backlight, and the aspect described above. 1 to 9, and the backlight control unit may control the luminance of the backlight based on a signal output from the optical sensor.
  • the display device since the display device includes the optical sensor that can accurately detect the proximity of the surrounding object, the luminance of the backlight can be controlled according to the proximity of the surrounding object.
  • the display device since the display device includes an optical sensor that can accurately detect the color component (illuminance information) of the ambient light, the brightness of the screen can be accurately controlled according to the illuminance of the ambient light. .
  • the backlight control unit may control the luminance of the backlight based on the digital value.
  • the optical sensor according to each aspect of the present invention may be realized by a computer.
  • the optical sensor is realized by the computer by operating the computer as each unit included in the optical sensor.
  • a control program and a computer-readable recording medium on which the control program is recorded also fall within the scope of the present invention.
  • the present invention can also be used to control the brightness of a backlight provided in a mobile phone or a digital camera.

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Abstract

In order to provide an optical sensor wherein adverse effects due to light to be disturbance can be suppressed in proximity detection and illuminance measurement, an optical sensor (1) is provided with: a light receiving element group (PDG) including a plurality of light receiving elements, which receive light and generate a photocurrent; a light receiving element selecting unit (11) that selects a light receiving element; a spectroscopic characteristic setting unit (12) that sets spectroscopic characteristics of the light receiving elements; and a light receiving quantity calculating unit (13), which receives the photocurrent generated by means of the light receiving element, and calculates a light receiving quantity.

Description

光センサおよび表示装置Optical sensor and display device
　本発明は、近接検知や照度測定に利用する光センサなどに関する。 The present invention relates to an optical sensor used for proximity detection and illuminance measurement.
　携帯電話やデジタルカメラなどの携帯端末は、液晶パネルを情報の表示装置として利用している。このような携帯端末では、近接センサを搭載することにより、ユーザーが携帯端末に顔を近づけた状況などを検知し、液晶パネルの表示を抑制し、携帯端末を低消費電力化させたいといった要望が増えている。 Mobile terminals such as mobile phones and digital cameras use liquid crystal panels as information display devices. In such a portable terminal, by installing a proximity sensor, there is a demand for detecting a situation where a user brings a face close to the portable terminal, suppressing display on the liquid crystal panel, and reducing power consumption of the portable terminal. is increasing.
　また、上述の携帯端末では、照度センサを搭載することにより、液晶パネルが利用されている環境の照度を測定し、測定結果に応じて液晶パネルが備えるバックライトの発光量を制御し、外乱光の下であっても液晶パネルに表示される情報の視認性を向上させたいといった要望がある。 In addition, the above-described mobile terminal is equipped with an illuminance sensor to measure the illuminance of the environment where the liquid crystal panel is used, and to control the amount of light emitted from the backlight included in the liquid crystal panel according to the measurement result. There is a desire to improve the visibility of information displayed on the liquid crystal panel even under the screen.
　さらに、上述の近接センサおよび照度センサを搭載した携帯端末を小型化したいといった要望から、近接・照度一体型センサが、近年、提案されている。 Furthermore, in recent years, a proximity / illuminance integrated sensor has been proposed in order to reduce the size of a portable terminal equipped with the proximity sensor and illuminance sensor described above.
　図１５は、特許文献１に記載の従来技術に係る光センサの要部を示す回路図である。図１５に示すように、特許文献１に記載の光センサは、分光特性（分光感度特性）が異なる２つの受光素子ＰＤ１、ＰＤ２、およびカレントミラー回路を備えており、カレントミラー回路を介して受光素子ＰＤ１が発生させる光電流Ｉｉｎ１の振幅をα倍した電流α・Ｉｉｎ１を取得し、これを受光素子ＰＤ２が発生させる光電流Ｉｉｎ２から減算し、電流（Ｉｉｎ２－α・Ｉｉｎ１）を得る。これにより、該光センサの分光特性は、各受光素子の分光特性を組み合わせた分光特性になる。 FIG. 15 is a circuit diagram showing the main part of the optical sensor according to the prior art described in Patent Document 1. As shown in FIG. 15, the optical sensor described in Patent Document 1 includes two light receiving elements PD1 and PD2 having different spectral characteristics (spectral sensitivity characteristics) and a current mirror circuit, and receives light via the current mirror circuit. A current α · Iin1 obtained by multiplying the amplitude of the photocurrent Iin1 generated by the element PD1 by α is obtained and subtracted from the photocurrent Iin2 generated by the light receiving element PD2 to obtain a current (Iin2-α · Iin1). Thereby, the spectral characteristic of the photosensor becomes a spectral characteristic that combines the spectral characteristics of the respective light receiving elements.
　また、該光センサでは、受光素子ＰＤ１を受光素子ＰＤ２で挟むように配置する。これにより、受光素子への入射光の光量が均一でない場合でも、受光素子から発生する光電流の偏りが低減される。 Further, in the optical sensor, the light receiving element PD1 is disposed so as to be sandwiched between the light receiving elements PD2. Thereby, even when the amount of incident light to the light receiving element is not uniform, the bias of the photocurrent generated from the light receiving element is reduced.
　図１６は、特許文献２に記載の従来技術に係る光センサの要部を示す平面図である。図１６に示すように、特許文献２に記載の光センサは、平面的に均等に配された分光特性が異なる２つの受光素子ＰＤ１、ＰＤ２を備えており、受光素子ＰＤ１から発生する光電流と、受光素子ＰＤ２から発生する光電流とを直接減算した電流を取得する。これにより、該光センサの分光特性は、各受光素子の分光特性を組み合わせた分光特性になる。 FIG. 16 is a plan view showing a main part of a conventional optical sensor described in Patent Document 2. FIG. As shown in FIG. 16, the optical sensor described in Patent Document 2 includes two light receiving elements PD1 and PD2 that are equally distributed in a plane and have different spectral characteristics, and a photocurrent generated from the light receiving element PD1. Then, a current obtained by directly subtracting the photocurrent generated from the light receiving element PD2 is obtained. Thereby, the spectral characteristic of the photosensor becomes a spectral characteristic that combines the spectral characteristics of the respective light receiving elements.
　また、該光センサでは、受光素子ＰＤ１、ＰＤ２が、それぞれ平面的に均等に配されており、受光素子への入射光の角度が偏っている場合でも、受光素子から発生する光電流の偏りが低減される。 In the optical sensor, the light receiving elements PD1 and PD2 are evenly arranged in a plane, and even if the angle of incident light to the light receiving element is biased, the photocurrent generated from the light receiving element is biased. Reduced.
日本国公開特許公報「特開２００７－７３５９１号（２００７年３月２２日公開）」Japanese Patent Publication “Japanese Patent Laid-Open No. 2007-73591 (published March 22, 2007)” 日本国公開特許公報「特開２００９－１８２１８９号（２００９年８月１３日公開）」Japanese Patent Publication “JP 2009-182189 (released on August 13, 2009)”
　光センサは、発光素子から出射された光を物体に反射させ、反射光を受光素子で受光することにより、物体が近接していることを検知する。このような光センサは、例えば携帯端末の筐体の内部に組み込まれ利用されることがある。この場合、発光素子から出射された光が筐体により反射され、該反射光を受光素子が受光することがある。 The light sensor reflects the light emitted from the light emitting element to the object and receives the reflected light by the light receiving element, thereby detecting that the object is close. Such an optical sensor may be used by being incorporated in a casing of a mobile terminal, for example. In this case, the light emitted from the light emitting element may be reflected by the housing, and the light receiving element may receive the reflected light.
　上述の従来技術に係る光センサでは、このような外乱となる反射光を受光素子が受光する可能性は考慮されておらず、該光センサは、近接を検知すべき物体からの反射光と筐体からの反射光とを判別できず、物体の近接を正確に検知できないといった問題がある。 In the above-described conventional optical sensor, the possibility that the light receiving element receives such reflected light as a disturbance is not taken into consideration, and the optical sensor does not reflect the reflected light from the object whose proximity should be detected. There is a problem that the reflected light from the body cannot be distinguished and the proximity of the object cannot be detected accurately.
　また、上述の従来技術に係る光センサでは、受光素子の分光特性や配置位置が固定されているため、受光素子への入射光の光量が均一でない場合や、受光素子への入射光の角度が偏っている場合、受光素子から発生する光電流の偏りが充分に低減されない。例えば、図１６に示すように、該光センサでは、受光素子ＰＤ１、ＰＤ２が光の入射範囲（レンズスポット）の中へ平面的に均等に含まれるように構成されているが、レンズスポットがずれた場合には、受光素子から発生する光電流に偏りが生じる。 Further, in the above-described conventional optical sensor, the spectral characteristics and the arrangement position of the light receiving element are fixed. Therefore, when the amount of incident light to the light receiving element is not uniform, or the angle of the incident light to the light receiving element is If it is biased, the bias of the photocurrent generated from the light receiving element is not sufficiently reduced. For example, as shown in FIG. 16, the light sensor is configured such that the light receiving elements PD1 and PD2 are uniformly included in a plane of incidence (lens spot) of the light, but the lens spot is shifted. In this case, the photocurrent generated from the light receiving element is biased.
　つまり、上述の従来技術に係る光センサでは、このような外乱となるレンズスポットがずれた光を受光素子が受光する可能性は充分に考慮されておらず、該光センサは、照度を正確に測定できないといった問題がある。 That is, in the optical sensor according to the above-described prior art, the possibility that the light receiving element receives the light with the lens spot shifted as a disturbance is not sufficiently considered, and the optical sensor accurately determines the illuminance. There is a problem that it cannot be measured.
　本発明は、上述の問題に鑑みてなされたもので、近接検知や照度測定において、外乱となる光に起因する悪影響を抑制することができる光センサを提供することを目的とする。 The present invention has been made in view of the above-described problems, and an object of the present invention is to provide an optical sensor capable of suppressing adverse effects caused by disturbance light in proximity detection and illuminance measurement.
　上記の課題を解決するために、本発明の一態様に係る光センサは、基板を有し、受光量を測定する光センサであって、上記基板上に配された、受光して光電流を発生させる複数の受光素子と、上記複数の受光素子のうち、一部の受光素子を選択する受光素子選択手段と、上記複数の受光素子の分光特性をそれぞれ設定する分光特性設定手段と、上記受光素子選択手段により選択され、かつ、上記分光特性設定手段により分光特性が設定された受光素子から発生した光電流を待ち受け、上記受光量を計算する受光量計算手段とを備えている。 In order to solve the above problems, an optical sensor according to one embodiment of the present invention includes a substrate and measures an amount of received light, and the photosensor is arranged on the substrate and receives photocurrent. A plurality of light-receiving elements to be generated; a light-receiving element selecting unit that selects a part of the plurality of light-receiving elements; a spectral characteristic setting unit that sets a spectral characteristic of each of the plurality of light-receiving elements; Receiving light amount calculating means for waiting for a photocurrent generated from the light receiving element selected by the element selecting means and having spectral characteristics set by the spectral characteristic setting means, and calculating the received light amount.
　本発明の一態様によれば、近接検知や照度測定において、外乱となる光に起因する悪影響を抑制することができる効果を奏する。 According to one aspect of the present invention, in proximity detection and illuminance measurement, it is possible to suppress an adverse effect caused by disturbing light.
本発明の一実施形態に係る光センサの構成を示す平面図である。It is a top view which shows the structure of the optical sensor which concerns on one Embodiment of this invention. 図１に示す光センサの受光素子の構成を示す断面図である。It is sectional drawing which shows the structure of the light receiving element of the optical sensor shown in FIG. 図１に示す光センサが近接検知に利用される際の動作を示す平面図である。It is a top view which shows operation | movement at the time of the optical sensor shown in FIG. 1 being utilized for proximity detection. 図１に示す光センサが近接検知に利用される際の動作を示す断面図である。It is sectional drawing which shows operation | movement at the time of the optical sensor shown in FIG. 1 being utilized for proximity detection. 図１に示す光センサが近接検知に利用される際の他の動作を示す断面図である。It is sectional drawing which shows another operation | movement at the time of the optical sensor shown in FIG. 1 being utilized for proximity detection. 図１に示す光センサの比較例に係る光センサが近接検知に利用される際の動作を示す断面図である。It is sectional drawing which shows operation | movement when the optical sensor which concerns on the comparative example of the optical sensor shown in FIG. 1 is utilized for proximity detection. 図１に示す光センサが照度測定に利用される際の動作を示す平面図である。It is a top view which shows operation | movement when the optical sensor shown in FIG. 1 is utilized for illumination intensity measurement. 図１に示す光センサが照度測定に利用される際の受光素子の分光特性を示すグラフである。It is a graph which shows the spectral characteristic of the light receiving element when the optical sensor shown in FIG. 1 is utilized for illumination intensity measurement. 本発明の他の実施形態に係る光センサの要部の構成を示す平面図である。It is a top view which shows the structure of the principal part of the optical sensor which concerns on other embodiment of this invention. 図９に示す光センサの要部の他の構成を示す平面図である。It is a top view which shows the other structure of the principal part of the optical sensor shown in FIG. 図９および図１０中に示すアナログ‐デジタル変換部の変形例の構成を示す図である。It is a figure which shows the structure of the modification of the analog-digital conversion part shown in FIG. 9 and FIG. 図１１に示すアナログ‐デジタル変換部の動作を示す波形図である。It is a wave form diagram which shows the operation | movement of the analog-digital conversion part shown in FIG. 図９～図１１中に示すアナログ‐デジタル変換部が近接検知において出力するデジタル信号などの波形図であり、（ａ）は物体の近接を検知した場合を示し、（ｂ）は物体の非近接を検知した場合を示す図である。FIG. 12 is a waveform diagram of a digital signal or the like output in proximity detection by the analog-digital conversion unit shown in FIGS. 9 to 11, where (a) shows a case where proximity of an object is detected, and (b) is non-proximity of the object It is a figure which shows the case where it detects. 本発明の他の実施形態に係る表示装置の概略構成を示すブロック図である。It is a block diagram which shows schematic structure of the display apparatus which concerns on other embodiment of this invention. 従来技術に係る光センサの要部を示す回路図である。It is a circuit diagram which shows the principal part of the optical sensor which concerns on a prior art. 従来技術に係る光センサの要部を示す平面図である。It is a top view which shows the principal part of the optical sensor which concerns on a prior art.
　以下、本発明の実施の形態について詳細に説明する。 Hereinafter, embodiments of the present invention will be described in detail.
　〔実施形態１〕
　本発明の一実施形態について、図１～図８に基づいて説明する。 [Embodiment 1]
An embodiment of the present invention will be described with reference to FIGS.
　＜光センサ１の構成＞
　図１は、本発明の一実施形態に係る光センサ１の構成を示す平面図である。図１に示すように、光センサ１は、受光素子群ＰＤＧと、制御部１０とを備えている。 <Configuration of optical sensor 1>
FIG. 1 is a plan view showing a configuration of an optical sensor 1 according to an embodiment of the present invention. As shown in FIG. 1, the optical sensor 1 includes a light receiving element group PDG and a control unit 10.
　ここで、受光素子群ＰＤＧは、基板（図４にて後述）上に配された１６個の受光素子（ＰＤ１１～１４、２１～２４、３１～３４、４１～４４）を含んでいる。なお、以下の記載において「受光素子ＰＤ」とは、この１６個の受光素子のいずれか１個を意味する。また、図１に示す構成に限定されるわけではなく、受光素子群ＰＤＧは、少なくとも２個、つまり複数の受光素子を含んでいればよい。また、領域Ｄは、１６個の受光素子を配した基板上の領域を表している。 Here, the light receiving element group PDG includes 16 light receiving elements (PDs 11 to 14, 21 to 24, 31 to 34, 41 to 44) arranged on a substrate (described later in FIG. 4). In the following description, “light receiving element PD” means any one of the 16 light receiving elements. Further, the configuration is not limited to the configuration illustrated in FIG. 1, and the light receiving element group PDG only needs to include at least two, that is, a plurality of light receiving elements. A region D represents a region on the substrate on which 16 light receiving elements are arranged.
　また、制御部１０は、受光素子選択部（受光素子選択手段）１１と、分光特性設定部（分光特性設定手段）１２と、受光量計算部（受光量計算手段）１３とを備えている。 The control unit 10 includes a light receiving element selecting unit (light receiving element selecting unit) 11, a spectral characteristic setting unit (spectral characteristic setting unit) 12, and a received light amount calculating unit (received light amount calculating unit) 13.
　そして、光が外部から例えば光スポットＳで示す範囲に入射している間に、光センサは、各受光素子から発生する光電流に基づいて、該光の受光量を測定する。なお、Ｘ軸およびＹ軸の方向は、領域Ｄが広がる平面を表す方向であり、Ｚ軸の方向は、各受光素子の受光面の法線方向であって、これらは、他の図面に示すＸ～Ｚ軸の方向に対応している。以下では、まず、受光素子ＰＤについて詳細に説明する。 Then, while the light is incident from the outside, for example, in a range indicated by the light spot S, the light sensor measures the amount of light received based on the photocurrent generated from each light receiving element. The directions of the X axis and the Y axis are directions representing a plane in which the region D is widened, and the direction of the Z axis is a normal direction of the light receiving surface of each light receiving element, which are shown in other drawings. Corresponds to the X to Z axis directions. Hereinafter, first, the light receiving element PD will be described in detail.
　（受光素子ＰＤ）
　図２は、図１に示す光センサ１の受光素子ＰＤの構成を示す断面図である。図２に示すように、受光素子ＰＤは、Ｐ基板（Ｐｓｕｂ）－Ｎウェル（Ｎｗｅｌｌ）－Ｐ拡散（Ｐｄｉｆ）の構成を有し、Ｐ基板（Ｐｓｕｂ）とＮウェル（Ｎｗｅｌｌ）とのＰＮ接合からなる赤外光受光用ＰＮ接合ＰＤｉｒと、Ｐ拡散（Ｐｄｉｆ）とＮウェル（Ｎｗｅｌｌ）とのＰＮ接合からなる可視光受光用ＰＮ接合ＰＤｖｉｓと、切替部ＳＷＳとを備えている。 (Light receiving element PD)
FIG. 2 is a cross-sectional view showing the configuration of the light receiving element PD of the optical sensor 1 shown in FIG. As shown in FIG. 2, the light receiving element PD has a configuration of P substrate (Psub) -N well (Nwell) -P diffusion (Pdif), and a PN junction between the P substrate (Psub) and the N well (Nwell). A PN junction PDir for receiving infrared light, a visible light receiving PN junction PDvis consisting of a PN junction of P diffusion (Pdif) and N well (Nwell), and a switching unit SWS.
　ここで、切替部ＳＷＳは、スイッチＳＷａおよびスイッチＳＷｂを備えている。また、切替部ＳＷＳは、分光特性設定部１２（図１参照）と接続されており、分光特性設定部１２は、各スイッチのＯＮ／ＯＦＦを切り替える。これにより、分光特性設定部１２は、受光素子ＰＤの分光特性を設定する。 Here, the switching unit SWS includes a switch SWa and a switch SWb. The switching unit SWS is connected to the spectral characteristic setting unit 12 (see FIG. 1), and the spectral characteristic setting unit 12 switches ON / OFF of each switch. Thereby, the spectral characteristic setting unit 12 sets the spectral characteristic of the light receiving element PD.
　なお、「受光素子ＰＤの分光特性」とは、一定光量の光の波長と、受光素子ＰＤが該光を受光し発生させる入力電流（光電流）Ｉｉｎの大きさとの関係を意味する。また、「受光素子ＰＤの分光特性を設定する」とは、所定の範囲に含まれる波長に対して、受光素子ＰＤが該波長かつ一定光量の光を受光し発生させる入力電流Ｉｉｎの大きさを設定することを意味する。以下では、受光素子ＰＤが備える各要素について詳細に説明する。 The “spectral characteristic of the light receiving element PD” means the relationship between the wavelength of light of a certain amount of light and the magnitude of the input current (photocurrent) Iin that the light receiving element PD receives and generates the light. Further, “setting the spectral characteristics of the light receiving element PD” means that the magnitude of the input current Iin that the light receiving element PD receives and generates light of a certain amount of light with respect to a wavelength included in a predetermined range. It means setting. Below, each element with which light receiving element PD is provided is demonstrated in detail.
　（赤外光受光用ＰＮ接合ＰＤｉｒ）
　赤外光受光用ＰＮ接合ＰＤｉｒは、赤外の分光特性を有する。これは、受光素子ＰＤに入射する光に含まれる赤外光が、可視光と比較して受光素子ＰＤのより深層（Ｚ軸の負方向）側まで伝播するためである。 (Infrared light receiving PN junction PDir)
The infrared light receiving PN junction PDir has infrared spectral characteristics. This is because infrared light included in the light incident on the light receiving element PD propagates to a deeper layer (negative direction of the Z axis) of the light receiving element PD as compared with visible light.
　なお、「赤外の分光特性」とは、赤外光受光用ＰＮ接合ＰＤｉｒが一定光量の赤外光を受光し発生させる光電流の大きさが、赤外光受光用ＰＮ接合ＰＤｉｒが該一定光量の光であって赤外光ではない光を受光し発生させる光電流の大きさよりも大きくなるような、赤外光受光用ＰＮ接合ＰＤｉｒが受光する光の波長と、発生させる光電流の大きさとの関係を意味する。 The “infrared spectral characteristics” means that the magnitude of the photocurrent generated by the infrared light receiving PN junction PDir receiving and generating a fixed amount of infrared light is the same as that of the infrared light receiving PN junction PDir. The wavelength of the light received by the PN junction PDir for receiving infrared light, which is larger than the magnitude of the photocurrent generated by receiving light of light quantity and not infrared light, and the magnitude of the generated photocurrent Means the relationship.
　（可視光受光用ＰＮ接合ＰＤｖｉｓ）
　可視光受光用ＰＮ接合ＰＤｖｉｓは、可視の分光特性を有する。これは、受光素子ＰＤに入射する光に含まれる可視光が、赤外光ほど受光素子ＰＤの深層側まで伝播しないためである。 (Visible light receiving PN junction PDvis)
The visible light receiving PN junction PDvis has visible spectral characteristics. This is because visible light included in the light incident on the light receiving element PD does not propagate to the deep layer side of the light receiving element PD as much as infrared light.
　なお、「可視の分光特性」とは、可視光受光用ＰＮ接合ＰＤｖｉｓが一定光量の可視光を受光し発生させる光電流の大きさが、可視光受光用ＰＮ接合ＰＤｖｉｓが該一定光量の光であって可視光ではない光を受光し発生させる光電流の大きさよりも大きくなるような、可視光受光用ＰＮ接合ＰＤｖｉｓが受光する光の波長と光電流の大きさとの関係を意味する。 The “visible spectral characteristic” means that the magnitude of the photocurrent generated by the visible light receiving PN junction PDvis receiving and generating a certain amount of visible light is the same as the visible light receiving PN junction PDvis. This means the relationship between the wavelength of light received by the visible light receiving PN junction PDvis and the magnitude of the photocurrent, which is larger than the magnitude of the photocurrent generated by receiving light that is not visible light.
　（切替部ＳＷＳ）
　切替部ＳＷＳは、スイッチＳＷａおよびスイッチＳＷｂを利用し、赤外光受光用ＰＮ接合ＰＤｉｒと、可視光受光用ＰＮ接合ＰＤｖｉｓとの接続状態を切り替える。 (Switching unit SWS)
The switching unit SWS uses the switch SWa and the switch SWb to switch the connection state between the infrared light receiving PN junction PDir and the visible light receiving PN junction PDvis.
　スイッチＳＷａは、ノードＮ０とノードＮ２との間に接続されている。また、ノードＮ０は、ノードＮ１を介して、可視光受光用ＰＮ接合ＰＤｖｉｓのカソードと接続されている。また、ノードＮ２は、可視光受光用ＰＮ接合ＰＤｖｉｓのアノードと接続されている。よって、スイッチＳＷａがＯＮされるとともに、スイッチＳＷｂがＯＦＦされた場合、可視光受光用ＰＮ接合ＰＤｖｉｓのカソードおよびアノードの電位が同一となるため、可視光受光用ＰＮ接合ＰＤｖｉｓから光電流が発生しなくなり、赤外光受光用ＰＮ接合ＰＤｉｒから発生する光電流のみが、ノードＮ０に入力電流Ｉｉｎとして出力される。これにより、受光素子ＰＤの分光特性を、赤外の分光特性にすることができる。 The switch SWa is connected between the node N0 and the node N2. The node N0 is connected to the cathode of the visible light receiving PN junction PDvis through the node N1. The node N2 is connected to the anode of the visible light receiving PN junction PDvis. Therefore, when the switch SWa is turned on and the switch SWb is turned off, the potential of the cathode and the anode of the visible light receiving PN junction PDvis becomes the same, so that a photocurrent is generated from the visible light receiving PN junction PDvis. Only the photocurrent generated from the infrared light receiving PN junction PDir is output as the input current Iin to the node N0. Thereby, the spectral characteristics of the light receiving element PD can be changed to infrared spectral characteristics.
　なお、「赤外の分光特性」とは、受光素子ＰＤが一定光量の赤外光を受光し発生させる入力電流Ｉｉｎの大きさが、受光素子ＰＤが該一定光量の光であって赤外光ではない光を受光し発生させる入力電流Ｉｉｎの大きさよりも大きくなるような、受光素子ＰＤが受光する光の波長と、発生させる入力電流Ｉｉｎの大きさとの関係を意味する。 The “infrared spectral characteristics” means that the magnitude of the input current Iin that the light receiving element PD receives and generates a fixed amount of infrared light is that the light receiving element PD is the light of the constant light amount. This means the relationship between the wavelength of light received by the light receiving element PD and the magnitude of the input current Iin to be generated, which is larger than the magnitude of the input current Iin that is received and generated by the light.
　スイッチＳＷｂは、ノードＮ２とグランドとの間に接続されている。よって、スイッチＳＷａがＯＦＦされるとともに、スイッチＳＷｂがＯＮされた場合、可視光受光用ＰＮ接合ＰＤｖｉｓから発生する光電流と、赤外光受光用ＰＮ接合ＰＤｉｒから発生する光電流とを合算した電流が、ノードＮ０に入力電流Ｉｉｎとして出力される。これにより、受光素子ＰＤの分光特性を、可視～赤外の分光特性にすることができる。 The switch SWb is connected between the node N2 and the ground. Therefore, when the switch SWa is turned off and the switch SWb is turned on, a current obtained by adding the photocurrent generated from the visible light receiving PN junction PDvis and the photocurrent generated from the infrared light receiving PN junction PDir. Is output as the input current Iin to the node N0. As a result, the spectral characteristics of the light receiving element PD can be changed from visible to infrared.
　なお、「可視～赤外の分光特性」とは、受光素子ＰＤが一定光量の可視～赤外光を受光し発生させる入力電流Ｉｉｎの大きさが、受光素子ＰＤが該一定光量の光であって可視～赤外光ではない光を受光し発生させる入力電流Ｉｉｎの大きさよりも大きくなるような、受光素子ＰＤが受光する光の波長と、発生させる入力電流Ｉｉｎの大きさとの関係を意味する。 The “visible to infrared spectral characteristics” means that the magnitude of the input current Iin that is generated when the light receiving element PD receives visible to infrared light with a constant light amount is that the light receiving element PD receives the light with the constant light amount. This means the relationship between the wavelength of light received by the light receiving element PD and the magnitude of the input current Iin to be generated, which is larger than the magnitude of the input current Iin that is received and generated by light that is not visible to infrared light. .
　また、「可視～赤外光」とは、可視光または赤外光に含まれる光を意味する。以下では、図１に示す制御部１０に含まれる各要素について詳細に説明する。 Further, “visible to infrared light” means light included in visible light or infrared light. Below, each element contained in the control part 10 shown in FIG. 1 is demonstrated in detail.
　（受光素子選択部１１）
　受光素子選択部１１は、受光素子群ＰＤＧに含まれる複数の受光素子のうち、一部の受光素子を選択する。なお、受光素子選択部１１は、複数個の受光素子を選択してもよい。また、受光素子選択部１１は、受光量計算部１３と接続されており、選択した受光素子がどの受光素子であるのかを示す情報を受光量計算部１３に送信する。 (Light receiving element selection unit 11)
The light receiving element selection unit 11 selects some of the light receiving elements among the plurality of light receiving elements included in the light receiving element group PDG. Note that the light receiving element selection unit 11 may select a plurality of light receiving elements. The light receiving element selection unit 11 is connected to the received light amount calculation unit 13 and transmits information indicating which light receiving element is the selected light receiving element to the received light amount calculation unit 13.
　（分光特性設定部１２）
　分光特性設定部１２は、図２に示すように受光素子ＰＤが備える切替部ＳＷＳに接続されており、受光素子群ＰＤＧに含まれる１６個の受光素子の分光特性をそれぞれ設定する。なお、分光特性設定部１２は、複数個の受光素子の分光特性を一括して設定してもよい。また、分光特性設定部１２は、受光量計算部１３と接続されており、受光素子ＰＤに設定された分光特性がどのような分光特性であるのかを示す情報を受光量計算部１３に送信する。さらに、受光素子選択部１１と、分光特性設定部１２とは互いに接続されており、分光特性設定部１２は、受光素子選択部１１によって選択された受光素子に設定された分光特性がどのような分光特性であるのかを示す情報を受光量計算部１３に送信する。 (Spectral characteristic setting unit 12)
As shown in FIG. 2, the spectral characteristic setting unit 12 is connected to a switching unit SWS included in the light receiving element PD, and sets the spectral characteristics of 16 light receiving elements included in the light receiving element group PDG. The spectral characteristic setting unit 12 may collectively set the spectral characteristics of a plurality of light receiving elements. The spectral characteristic setting unit 12 is connected to the received light amount calculation unit 13 and transmits information indicating what spectral characteristic the spectral characteristic set in the light receiving element PD is to the received light amount calculation unit 13. . Further, the light receiving element selection unit 11 and the spectral characteristic setting unit 12 are connected to each other, and the spectral characteristic setting unit 12 determines what spectral characteristics are set for the light receiving element selected by the light receiving element selection unit 11. Information indicating whether the light has spectral characteristics is transmitted to the received light amount calculation unit 13.
　（受光量計算部１３）
　受光量計算部１３は、受光素子選択部１１により選択され、かつ、分光特性設定部１２により分光特性が設定された受光素子から発生した光電流を待ち受け、光センサ１が受光する光の受光量を計算する。 (Received light amount calculation unit 13)
The received light amount calculation unit 13 waits for a photocurrent generated from the light receiving element selected by the light receiving element selection unit 11 and whose spectral characteristics are set by the spectral characteristic setting unit 12, and receives the amount of light received by the optical sensor 1. Calculate
　＜光センサ１の動作＞
　上述の構成を備える光センサ１や光センサ１を利用した受光量の測定方法により、近接検知や照度測定において、外乱となる光に起因する悪影響を抑制することができる。以下では、光センサ１が近接検知および照度測定に利用される際の動作について、順に説明する。 <Operation of optical sensor 1>
With the optical sensor 1 having the above-described configuration and the method of measuring the amount of received light using the optical sensor 1, adverse effects caused by light that becomes a disturbance can be suppressed in proximity detection and illuminance measurement. Hereinafter, operations when the optical sensor 1 is used for proximity detection and illuminance measurement will be described in order.
　（近接検知における光センサ１の動作）
　図３は、図１に示す光センサ１が近接検知に利用される際の動作を示す平面図である。図３に示すように、光センサ１は、少なくとも赤外光を出射する発光素子ＬＥＤと、発光素子ＬＥＤを駆動するＬＥＤ駆動回路ＤＣを備えている。なお、発光素子ＬＥＤとして、発光ダイオード（Light Emitting Diode）を利用してもよい。また、光センサ１は、発光素子ＬＥＤを複数備えていてもよい。 (Operation of the optical sensor 1 in proximity detection)
FIG. 3 is a plan view showing an operation when the optical sensor 1 shown in FIG. 1 is used for proximity detection. As shown in FIG. 3, the optical sensor 1 includes a light emitting element LED that emits at least infrared light, and an LED drive circuit DC that drives the light emitting element LED. Note that a light emitting diode may be used as the light emitting element LED. The optical sensor 1 may include a plurality of light emitting elements LED.
　ここで、受光素子選択部１１（図１参照）は、受光素子群ＰＤＧに含まれる１６個の受光素子のうち、領域Ｄの発光素子側の領域Ｄａに配された一部の受光素子（ＰＤ１３、１４、２３、２４、３３、３４、４３、４４）を選択する。また、分光特性設定部１２（図１参照）は、受光素子選択部１１により選択された受光素子の分光特性として、赤外の分光特性を設定する。 Here, the light receiving element selection unit 11 (see FIG. 1), among the 16 light receiving elements included in the light receiving element group PDG, a part of the light receiving elements (PD13) arranged in the region Da on the light emitting element side of the region D. , 14, 23, 24, 33, 34, 43, 44). The spectral characteristic setting unit 12 (see FIG. 1) sets infrared spectral characteristics as the spectral characteristics of the light receiving element selected by the light receiving element selecting unit 11.
　通常、光が光スポットＳで示す範囲に入射するように、光センサ１は設計される。しかし、後述する原因により、他の光が光スポットＳａで示す範囲へさらに入射することがある。つまり、光スポットＳａで示す範囲へ入射する光は、外乱となる光であって、光センサ１が誤作動する原因になり得る光である。 Usually, the optical sensor 1 is designed so that light enters the range indicated by the light spot S. However, other light may further enter the range indicated by the light spot Sa due to the cause described later. That is, the light incident on the range indicated by the light spot Sa is light that causes disturbance, and can cause the optical sensor 1 to malfunction.
　しかしながら、このような場合であっても、光センサ１は、近接検知において、外乱となる光に起因する悪影響を抑制することができる。以下では、この原理について詳細に説明する。 However, even in such a case, the optical sensor 1 can suppress an adverse effect caused by light that becomes a disturbance in proximity detection. Hereinafter, this principle will be described in detail.
　（近接検知における光センサ１の動作原理）
　図４は、図１に示す光センサ１が近接検知に利用される際の動作を示す断面図である。図４に示すように、光センサ１は、発光素子ＬＥＤから出射された光を近接検知物体４１に反射させ、反射光を基板２１上に配された受光素子群ＰＤＧで受光することにより、近接検知物体４１が近接していることを検知する。このような光センサ１は、例えば携帯端末の筐体である携帯パネル筐体３１の内部に組み込まれ利用されることがある。なお、「携帯パネル筐体３１の内部」とは、図４において、携帯パネル筐体３１に対してＺ軸の負方向側の空間を意味する。そして、光センサ１は、携帯パネル筐体３１と間隔ｄを空けて、携帯パネル筐体３１の内部に組み込まれている。 (Operation principle of the optical sensor 1 in proximity detection)
FIG. 4 is a cross-sectional view showing an operation when the optical sensor 1 shown in FIG. 1 is used for proximity detection. As shown in FIG. 4, the optical sensor 1 reflects the light emitted from the light emitting element LED to the proximity detection object 41 and receives the reflected light by the light receiving element group PDG arranged on the substrate 21, thereby making the proximity It detects that the detection object 41 is approaching. Such an optical sensor 1 may be used by being incorporated in, for example, a mobile panel housing 31 that is a housing of a mobile terminal. Note that “inside the mobile panel casing 31” means a space on the negative side of the Z axis with respect to the mobile panel casing 31 in FIG. The optical sensor 1 is incorporated in the portable panel casing 31 with a distance d from the portable panel casing 31.
　ここで、発光素子ＬＥＤから出射され携帯パネル筐体３１で反射された筐体反射光が受光素子群ＰＤＧに入射し、受光素子群ＰＤＧは、発光素子ＬＥＤから出射され筐体外部の近接検知物体４１で反射された物体反射光が該受光素子に入射した場合に発生する光電流と同様の光電流を発生させることがある。この場合、従来技術における光センサは、筐体反射光と物体反射光とを判別できず、近接検知物体４１が該光センサに近接していなくても近接していると誤検知する。 Here, the case reflected light emitted from the light emitting element LED and reflected by the portable panel casing 31 enters the light receiving element group PDG, and the light receiving element group PDG is emitted from the light emitting element LED and is a proximity detection object outside the casing. A photocurrent similar to the photocurrent generated when the object reflected light reflected by 41 is incident on the light receiving element may be generated. In this case, the conventional optical sensor cannot distinguish between the case reflected light and the object reflected light, and erroneously detects that the proximity detection object 41 is close even if it is not close to the optical sensor.
　図５は、図１に示す光センサ１が近接検知に利用される際の他の動作を示す断面図である。図４に示す光センサ１が組み込まれた携帯端末が小型化された場合、図５に示すように、光センサ１と携帯パネル筐体３１との間隔ｄａは、図４に示す間隔ｄよりも狭くなる。このとき、筐体反射光が携帯パネル筐体３１となす角度θａは、図４に示す角度θよりも小さくなる。そして、図５に示す筐体反射光は、受光素子群ＰＤＧへ入射する際、図４に示す筐体反射光と比較して、発光素子ＬＥＤ側からＸ軸の負方向へより離れた位置へ入射する。ここで、光センサはより小型の携帯端末に組み込まれて利用される傾向にあるため、筐体反射光は、発光素子ＬＥＤ側からＸ軸の負方向へより離れた位置へ入射する可能性が高い。 FIG. 5 is a cross-sectional view showing another operation when the optical sensor 1 shown in FIG. 1 is used for proximity detection. When the portable terminal incorporating the optical sensor 1 shown in FIG. 4 is miniaturized, as shown in FIG. 5, the distance da between the optical sensor 1 and the portable panel housing 31 is larger than the distance d shown in FIG. Narrow. At this time, the angle θa formed by the case reflected light with the portable panel case 31 is smaller than the angle θ shown in FIG. Then, when the case reflected light shown in FIG. 5 enters the light receiving element group PDG, the case reflected light is further away from the light emitting element LED side in the negative direction of the X axis than the case reflected light shown in FIG. Incident. Here, since the optical sensor tends to be used by being incorporated in a smaller portable terminal, the reflected light from the casing may be incident on a position further away from the light emitting element LED side in the negative direction of the X axis. high.
　そして、光センサ１では、受光素子選択部１１（図１参照）が、受光素子群ＰＤＧに含まれる１６個の受光素子のうち、領域Ｄの発光素子ＬＥＤ側の領域Ｄａに配された一部の受光素子（図３参照）、つまり他の受光素子と比較して筐体反射光が入射する可能性が低い受光素子を選択するため、受光量計算部１３（図１参照）は、受光量の計算において、筐体反射光の影響を抑制できる。換言するならば、光センサ１は、領域Ｄに配された１６個の受光素子のうち、一部の受光素子を選択することで、物体反射光を積極的に受光するように光学特性を調整し、受光量の測定においてノイズとなる筐体反射光の受光量を低減することができる。 In the optical sensor 1, the light receiving element selection unit 11 (see FIG. 1) is a part of the 16 light receiving elements included in the light receiving element group PDG that is arranged in the area Da on the light emitting element LED side of the area D. In order to select the light receiving element (see FIG. 3), that is, the light receiving element that is less likely to receive the case reflected light than other light receiving elements, the received light amount calculation unit 13 (see FIG. 1) In this calculation, the influence of the case reflected light can be suppressed. In other words, the optical sensor 1 adjusts the optical characteristics so as to positively receive object reflected light by selecting some of the 16 light receiving elements arranged in the region D. In addition, it is possible to reduce the received light amount of the case reflected light that becomes noise in the measurement of the received light amount.
　（光センサ１の比較例）
　図６は、図１に示す光センサ１の比較例に係る光センサ１０１が近接検知に利用される際の動作を示す断面図である。図６に示すように、光センサ１０１は、遮蔽物１０２を備えている点が、光センサ１とは異なる。そして、光センサ１０１では、遮蔽物１０２により、筐体反射光が受光素子群ＰＤＧに入射することを防止する。しかしながら、光センサ１０１と携帯パネル筐体３１との間隔よりも、遮蔽物１０２のＺ軸方向の長さｄｂが大きい場合、光センサ１は、遮蔽物１０２を備えられない場合がある。そして、光センサはより小型の携帯端末に組み込まれて利用される傾向にあるため、比較例に係る構成は採用できないことが多い。また、遮蔽物１０２を光センサに組み込むことで増加するコストを許容できない可能性もある。 (Comparative example of the optical sensor 1)
FIG. 6 is a cross-sectional view showing an operation when the optical sensor 101 according to the comparative example of the optical sensor 1 shown in FIG. 1 is used for proximity detection. As shown in FIG. 6, the optical sensor 101 is different from the optical sensor 1 in that it includes a shielding object 102. In the optical sensor 101, the shield 102 prevents the case reflected light from entering the light receiving element group PDG. However, when the length db in the Z-axis direction of the shield 102 is larger than the distance between the photosensor 101 and the mobile panel housing 31, the photosensor 1 may not be provided with the shield 102. And since an optical sensor tends to be incorporated and used in a smaller portable terminal, the configuration according to the comparative example cannot often be employed. In addition, there is a possibility that the increased cost of incorporating the shielding object 102 into the optical sensor cannot be allowed.
　（近接検知における外乱光の下での光センサ１の動作）
　光センサ１は、例えば蛍光灯などから出射された可視光が受光素子ＰＤに入射する環境下で利用されることがある。しかしながら、このような場合でも、分光特性設定部１２（図１参照）は、受光素子選択部１１（図１参照）により選択された受光素子の分光特性として、赤外の分光特性を設定するので、該受光素子は、可視光に起因する光電流の発生を抑制し、発光素子ＬＥＤ（図３参照）から出射された赤外光を選択的に受光して光電流を発生させる。よって、受光量計算部１３（図１参照）は、受光量の計算において、可視光の影響を抑制できる。このように、光センサ１は、可視光に起因する誤検知を抑制できるため、近接検知に適している。 (Operation of the optical sensor 1 under disturbance light in proximity detection)
The optical sensor 1 may be used in an environment where, for example, visible light emitted from a fluorescent lamp enters the light receiving element PD. However, even in such a case, the spectral characteristic setting unit 12 (see FIG. 1) sets the infrared spectral characteristic as the spectral characteristic of the light receiving element selected by the light receiving element selection unit 11 (see FIG. 1). The light receiving element suppresses generation of a photocurrent caused by visible light, and selectively receives infrared light emitted from the light emitting element LED (see FIG. 3) to generate a photocurrent. Therefore, the received light amount calculation unit 13 (see FIG. 1) can suppress the influence of visible light in the calculation of the received light amount. Thus, the optical sensor 1 is suitable for proximity detection because it can suppress erroneous detection due to visible light.
　すなわち、光センサは、筐体反射光に起因する悪影響を抑制可能であるとともに、近接検知に好適である。 That is, the optical sensor can suppress adverse effects caused by the reflected light from the housing and is suitable for proximity detection.
　（照度測定における光センサ１の動作）
　図７は、図１に示す光センサ１が照度測定に利用される際の動作を示す平面図である。図７に示すように、受光素子選択部１１（図１参照）は、受光素子群ＰＤＧに含まれる１６個の受光素子のうち、領域Ｄの中心付近の一部の領域Ｄｂに配された受光素子（ＰＤ２２、２３、３２、３３）を選択する。また、分光特性設定部１２（図１参照）は、受光素子選択部１１により選択された受光素子の分光特性として、可視～赤外の分光特性と、赤外の分光特性とのいずれかを選択する。そして、受光量計算部１３（図１参照）は、分光特性設定部１２により可視～赤外の分光特性が設定されている間に該受光素子から発生する光電流の大きさから、分光特性設定部１２により赤外の分光特性が設定されている間に該受光素子から発生する光電流の大きさを減算して、受光量を計算する。 (Operation of the optical sensor 1 in illuminance measurement)
FIG. 7 is a plan view showing an operation when the optical sensor 1 shown in FIG. 1 is used for illuminance measurement. As shown in FIG. 7, the light receiving element selection unit 11 (see FIG. 1) receives the light received in a part of the region Db near the center of the region D among the 16 light receiving elements included in the light receiving element group PDG. The element (PD22, 23, 32, 33) is selected. The spectral characteristic setting unit 12 (see FIG. 1) selects either the visible to infrared spectral characteristic or the infrared spectral characteristic as the spectral characteristic of the light receiving element selected by the light receiving element selecting unit 11. To do. The received light amount calculation unit 13 (see FIG. 1) sets the spectral characteristic from the magnitude of the photocurrent generated from the light receiving element while the spectral characteristic setting unit 12 sets the visible to infrared spectral characteristic. While the infrared spectral characteristic is set by the unit 12, the magnitude of the photocurrent generated from the light receiving element is subtracted to calculate the amount of received light.
　通常、光が光スポットＳで示す範囲に入射するように、光センサ１は設計される。しかし、レンズなどの光学系の構成に起因して、光が光スポットＳｂで示す範囲にずれて入射することがある。つまり、光スポットＳｂで示す範囲に入射する光の一部は、外乱となる光であって、光センサ１が誤作動する原因になり得る。 Usually, the optical sensor 1 is designed so that light enters the range indicated by the light spot S. However, due to the configuration of the optical system such as the lens, the light may be incident on the range indicated by the light spot Sb. That is, part of the light incident on the range indicated by the light spot Sb is a disturbance light and may cause the optical sensor 1 to malfunction.
　しかしながら、このような場合であっても、光センサ１は、照度測定において、外乱となる光に起因する悪影響を抑制することができる。以下では、この原理について詳細に説明する。 However, even in such a case, the optical sensor 1 can suppress an adverse effect caused by the disturbing light in the illuminance measurement. Hereinafter, this principle will be described in detail.
　（照度測定における光センサ１の動作原理）
　通常、複数の受光素子が配された領域（受光領域）へ、光センサの外部から入射する光（環境光）の強度分布の重心（入射中心）と、受光領域の中心（受光中心）とが一致するように、光センサは設計される。例えば、図７などに示す光スポットＳで示す範囲に光が入射するように、光センサ１は設計される。しかし、光センサに作用する外力や経年劣化などにより、各中心がずれることがある。このため、従来技術に係る光センサは、設計された通りに、光センサが置かれた環境の照度を測定できないことがある。 (Operation principle of the optical sensor 1 in illuminance measurement)
Normally, the center of gravity (incident center) of the intensity distribution of light (environmental light) incident from the outside of the optical sensor and the center of the light receiving area (light receiving center) into the area where the plurality of light receiving elements are arranged (light receiving area) The optical sensor is designed to match. For example, the optical sensor 1 is designed so that light enters the range indicated by the light spot S shown in FIG. However, each center may be shifted due to external force acting on the optical sensor or aging deterioration. For this reason, the optical sensor according to the related art may not be able to measure the illuminance of the environment where the optical sensor is placed as designed.
　ここで、各中心がずれる場合、入射中心が受光中心からランダムな方向へ移動した位置へずれると予想されるため、期待される入射中心は、受光中心に一致する。例えば、図７に示すように、光センサ１では、光が光スポットＳでなく光スポットＳｂで示す範囲にずれて入射した場合であっても、光スポットＳｂは、領域Ｄの中心付近の一部の領域Ｄｂを含むと期待される。 Here, when each center is deviated, since the incident center is expected to shift to a position moved in a random direction from the light receiving center, the expected incident center coincides with the light receiving center. For example, as shown in FIG. 7, in the optical sensor 1, the light spot Sb is a part of the vicinity of the center of the region D even when the light is incident on the light spot Sb instead of the light spot S. It is expected to include a partial region Db.
　そして、光センサ１では、受光素子選択部１１（図１参照）によって、受光素子群ＰＤＧに含まれる１６個の受光素子のうち、領域Ｄの中心付近の領域Ｄｂに配された一部の受光素子、つまり他の受光素子と比較して環境光が入射する可能性が高い受光素子が選択されることにより、受光量計算部１３（図１参照）は、受光量の計算において、入射中心のずれの影響を抑制できる。換言するならば、光センサ１は、領域Ｄに配された１６個の受光素子のうち、一部の受光素子を選択することで、環境光を積極的に受光するように光学特性を調整し、受光した光の受光量に対して光センサ１が実際に測定結果として出力する該光の受光量を表す感度のばらつきを少なくすることができる。 In the optical sensor 1, the light receiving element selection unit 11 (see FIG. 1) receives a part of the light received in the region Db near the center of the region D among the 16 light receiving elements included in the light receiving element group PDG. By selecting an element, that is, a light receiving element that is more likely to receive ambient light than other light receiving elements, the received light amount calculation unit 13 (see FIG. 1) The influence of deviation can be suppressed. In other words, the optical sensor 1 adjusts the optical characteristics so as to actively receive ambient light by selecting some of the 16 light receiving elements arranged in the region D. Thus, it is possible to reduce variations in sensitivity representing the amount of received light that is actually output as a measurement result by the optical sensor 1 with respect to the amount of received light.
　（照度測定における受光素子ＰＤの分光特性）
　図８は、図１に示す光センサ１が照度測定に利用される際の受光素子ＰＤの分光特性を示すグラフである。図８において、横軸は受光素子ＰＤに入射する光の波長を示し、縦軸は該光の光量をワット（Ｗ）、受光素子ＰＤから発生する光電流をアンペア（Ａ）で表わしたときの両者の比率を示す。図８に示すように、可視～赤外の分光特性から、赤外の分光特性をα倍して減算すると、視感度に近い分光特性になる。ここで、αの値は、既知の視感度に合致するように選択する。 (Spectral characteristics of light receiving element PD in illuminance measurement)
FIG. 8 is a graph showing the spectral characteristics of the light receiving element PD when the optical sensor 1 shown in FIG. 1 is used for illuminance measurement. In FIG. 8, the horizontal axis indicates the wavelength of light incident on the light receiving element PD, and the vertical axis indicates the amount of light in watts (W) and the photocurrent generated from the light receiving element PD in amperes (A). The ratio of both is shown. As shown in FIG. 8, when the infrared spectral characteristic is subtracted by α times from the visible to infrared spectral characteristic, the spectral characteristic close to the visibility is obtained. Here, the value of α is selected so as to match the known visibility.
　なお、「視感度」とは、所定の範囲に含まれる波長に対して、人の眼が該波長の光を受光した場合に、該人が視覚に感じる明るさの度合いを意味する。ここで、視感度は、可視光の波長の範囲（約４００～７００ｎｍ）の中央付近の波長に対して最大値をとり、該範囲の両端により近い波長に対してより小さい値をとる。 “Visibility” means the degree of brightness perceived by a person when the human eye receives light of the wavelength with respect to a wavelength included in a predetermined range. Here, the visual sensitivity takes a maximum value for the wavelength near the center of the visible light wavelength range (about 400 to 700 nm), and takes a smaller value for wavelengths closer to both ends of the range.
　また、「視感度に近い分光特性」とは、人の眼が受光する光の波長と、該人が視覚に感じる明るさの度合いとの関係に、分光特性が近いことを意味する。 Also, “spectral characteristics close to visual sensitivity” means that the spectral characteristics are close to the relationship between the wavelength of light received by the human eye and the degree of brightness that the person perceives visually.
　そして、光センサ１では、分光特性設定部１２（図１参照）が、受光素子ＰＤの分光特性として、可視～赤外の分光特性を設定している間、該受光素子は、可視～赤外光の受光量に応じた光電流を発生させる。また、分光特性設定部１２が、該受光素子の分光特性として、赤外の分光特性を設定している間、該受光素子は、赤外光の受光量に応じた光電流を発生させる。 In the optical sensor 1, while the spectral characteristic setting unit 12 (see FIG. 1) sets the visible to infrared spectral characteristic as the spectral characteristic of the light receiving element PD, the light receiving element is visible to infrared. A photocurrent corresponding to the amount of received light is generated. Further, while the spectral characteristic setting unit 12 sets the infrared spectral characteristic as the spectral characteristic of the light receiving element, the light receiving element generates a photocurrent corresponding to the amount of received infrared light.
　また、受光量計算部１３（図１参照）は、可視～赤外光の受光量に応じた光電流の大きさから、赤外光の受光量に応じた光電流の大きさを減算することで、可視光の受光量に応じた光電流の大きさを計算できる。このように、光センサ１は、視感度に近い分光特性を実現できるため、照度測定に適している。 The received light amount calculation unit 13 (see FIG. 1) subtracts the magnitude of the photocurrent according to the amount of received light of infrared light from the magnitude of the photocurrent according to the amount of received light of visible to infrared light. Thus, the magnitude of the photocurrent according to the amount of received visible light can be calculated. Thus, the optical sensor 1 is suitable for illuminance measurement because it can realize spectral characteristics close to the visibility.
　すなわち、光センサ１は、環境光の入射中心のずれに起因する悪影響を抑制可能であるとともに、照度測定に好適である。 That is, the optical sensor 1 can suppress an adverse effect caused by a shift in the incident center of ambient light and is suitable for illuminance measurement.
　＜光センサ１の効果＞
　光センサ１や光センサ１を利用した受光量の測定方法により、近接検知や照度測定において、外乱となる光に起因する悪影響を抑制することができる。 <Effect of optical sensor 1>
By the optical sensor 1 and the method for measuring the amount of received light using the optical sensor 1, adverse effects caused by the disturbing light can be suppressed in proximity detection and illuminance measurement.
　＜その他の光センサ１の構成、動作、および効果＞
　光センサ１は、図２に示す構成に限定されず、受光素子ＰＤは、互いに異なる分光特性を有する３つ以上のＰＮ接合を備えていてもよい。換言するならば、受光素子ＰＤが、赤外光受光用ＰＮ接合ＰＤｉｒおよび可視光受光用ＰＮ接合ＰＤｖｉｓ以外のＰＮ接合をさらに備えていてもよい。また、切替部ＳＷＳは、３つ以上のスイッチを利用し、各ＰＮ接合間の接続状態を切り替えてもよい。 <Configuration, operation, and effect of other optical sensor 1>
The optical sensor 1 is not limited to the configuration shown in FIG. 2, and the light receiving element PD may include three or more PN junctions having different spectral characteristics. In other words, the light receiving element PD may further include a PN junction other than the infrared light receiving PN junction PDir and the visible light receiving PN junction PDvis. The switching unit SWS may switch the connection state between the PN junctions using three or more switches.
　上記構成によれば、３つ以上のＰＮ接合が、受光素子ＰＤにより受光された光に含まれる光であって互いに異なる波長を有する３種以上の光の光量に応じた光電流を発生させるため、受光量計算部１３（図１参照）は、３種以上の光の光量に応じた光電流を、受光素子ＰＤから受けることができる。 According to the above configuration, three or more PN junctions generate photocurrents corresponding to the amounts of three or more types of light that are included in the light received by the light receiving element PD and have different wavelengths. The received light amount calculation unit 13 (see FIG. 1) can receive a photocurrent corresponding to the amount of light of three or more types from the light receiving element PD.
　すなわち、光センサ１は、近接検知や照度測定において、外乱となる多様な光に起因する悪影響を抑制することができる。 That is, the optical sensor 1 can suppress adverse effects caused by various kinds of light as disturbances in proximity detection and illuminance measurement.
　光センサ１は、図４に示すように、受光素子群ＰＤＧを封止する樹脂封止部２２をさらに備え、樹脂封止部２２は、基板２１上の受光素子群ＰＤＧが配された領域に光を集光するレンズ（レンズ形状）２３を有していてもよい。 As shown in FIG. 4, the optical sensor 1 further includes a resin sealing portion 22 that seals the light receiving element group PDG. The resin sealing portion 22 is located in a region on the substrate 21 where the light receiving element group PDG is disposed. You may have the lens (lens shape) 23 which condenses light.
　光センサが小型化され受光領域が狭くなった場合には、例えばレンズにより、光センサが受光する光を狭い領域に集光するといったことが行われる。換言するならば、レンズにより、光センサにレンズの光軸方向に対する高い指向性を持たせる。また、レンズにより、受光する光を狭い領域に集光する場合には、レンズの焦点を当該領域に一致させるといったことが行われる。このような場合には、レンズと光が集光される領域との相対的な位置関係が固定されていることが好ましい。 When the light sensor is downsized and the light receiving area becomes narrow, for example, the lens receives light received by the light sensor in a narrow area. In other words, the lens allows the optical sensor to have high directivity with respect to the optical axis direction of the lens. In addition, when the light received by the lens is collected in a narrow area, the focal point of the lens is matched with the area. In such a case, it is preferable that the relative positional relationship between the lens and the region where the light is collected is fixed.
　上記構成によれば、光センサ１が受光する光が、レンズ２３により受光領域に集光されるとともに、レンズ２３と受光領域との相対的な位置関係が固定されるので、受光領域が狭くなった場合であっても、受光素子ＰＤは正確に光を受光することができる。 According to the above configuration, the light received by the optical sensor 1 is condensed on the light receiving area by the lens 23 and the relative positional relationship between the lens 23 and the light receiving area is fixed, so that the light receiving area is narrowed. Even in this case, the light receiving element PD can accurately receive light.
　〔実施形態２〕
　本発明の他の実施形態について、図９～図１３に基づいて説明すれば、以下のとおりである。なお、説明の便宜上、上述の実施形態にて説明した部材と同じ機能を有する部材については、同じ符号を付記し、その説明を省略する。 [Embodiment 2]
The following will describe another embodiment of the present invention with reference to FIGS. For convenience of explanation, members having the same functions as those described in the above-described embodiment are denoted by the same reference numerals and description thereof is omitted.
　＜アナログ‐デジタル変換を利用する光センサ１の構成、動作、および効果＞
　図９は、本発明の他の実施形態に係る光センサ１の要部の構成を示す平面図である。図９に示すように、光センサ１は、領域Ｄａに含まれる受光素子ＰＤから発生する光電流Ｉａの大きさをデジタル値ＡＤＣＯＵＴａに変換するアナログ‐デジタル変換部（アナログ‐デジタル変換手段）ＡＤＣをさらに備えていてもよい。例えば、光センサ１では、制御部１０（図１参照）にアナログ‐デジタル変換部ＡＤＣを加えて制御部１０ａを構成してもよい。なお、光センサ１のその他の構成は、図３に示す近接検知に利用される光センサ１と同様である。 <Configuration, operation, and effect of optical sensor 1 using analog-digital conversion>
FIG. 9 is a plan view showing a configuration of a main part of an optical sensor 1 according to another embodiment of the present invention. As shown in FIG. 9, the optical sensor 1 includes an analog-to-digital conversion unit (analog-to-digital conversion means) ADC that converts the magnitude of the photocurrent Ia generated from the light receiving element PD included in the region Da into a digital value ADCOUTa. Furthermore, you may provide. For example, in the optical sensor 1, the controller 10a may be configured by adding an analog-digital converter ADC to the controller 10 (see FIG. 1). In addition, the other structure of the optical sensor 1 is the same as that of the optical sensor 1 utilized for the proximity detection shown in FIG.
　上記構成によれば、アナログ‐デジタル変換部ＡＤＣにより、各受光素子ＰＤの受光量に応じた光電流Ｉａの大きさをデジタル値ＡＤＣＯＵＴａに変換できる。すなわち、光センサ１は、近接検知において、所望のデジタル処理が可能な受光量を表すデジタル値を出力することができる。なお、光電流Ｉａは、分光特性設定部１２により赤外の分光特性が設定されている間に受光素子ＰＤから発生する光電流である。 According to the above configuration, the analog-digital conversion unit ADC can convert the magnitude of the photocurrent Ia corresponding to the amount of light received by each light receiving element PD into a digital value ADCOUTa. That is, the optical sensor 1 can output a digital value representing the amount of received light that can be subjected to desired digital processing in proximity detection. The photocurrent Ia is a photocurrent generated from the light receiving element PD while the infrared spectral characteristic is set by the spectral characteristic setting unit 12.
　図１０は、図９に示す光センサ１の要部の他の構成を示す平面図である。図１０に示すように、光センサ１は、受光素子ＰＤから発生する光電流ＩｂおよびＩｃの大きさをデジタル値に変換するアナログ‐デジタル変換部（アナログ‐デジタル変換手段）ＡＤＣをさらに複数備えていてもよい。例えば、光センサ１では、制御部１０（図１参照）にアナログ‐デジタル変換部ＡＤＣを２個加えて制御部１０ｂを構成し、受光量計算部１３（図１参照）において、第１のアナログ‐デジタル変換部ＡＤＣから出力されたデジタル値ＡＤＣＯＵＴｂと、第２のアナログ‐デジタル変換部ＡＤＣから出力されたデジタル値ＡＤＣＯＵＴｃを図示しない積算器によりα倍したデジタル値α・ＡＤＣＯＵＴｃとの減算を行うようにしてもよい。なお、光センサ１のその他の構成は、図７に示す照度測定に利用される光センサ１と同様である。 FIG. 10 is a plan view showing another configuration of the main part of the optical sensor 1 shown in FIG. As shown in FIG. 10, the optical sensor 1 further includes a plurality of analog-digital conversion units (analog-digital conversion means) ADCs that convert the magnitudes of the photocurrents Ib and Ic generated from the light receiving element PD into digital values. May be. For example, in the optical sensor 1, a controller 10b is configured by adding two analog-to-digital converters ADC to the controller 10 (see FIG. 1), and the received light amount calculator 13 (see FIG. 1) has a first analog signal. The subtraction between the digital value ADCOUTb output from the digital conversion unit ADC and the digital value α · ADCOUTc obtained by multiplying the digital value ADCOUTc output from the second analog-digital conversion unit ADC by α by a multiplier (not shown) is performed. It may be. In addition, the other structure of the optical sensor 1 is the same as that of the optical sensor 1 utilized for the illumination intensity measurement shown in FIG.
　上記構成によれば、アナログ‐デジタル変換部ＡＤＣにより、各受光素子ＰＤの受光量に応じた光電流ＩｂおよびＩｃの大きさをデジタル値（ＡＤＣＯＵＴｂ－α・ＡＤＣＯＵＴｃ）に変換できる。すなわち、光センサ１は、照度測定において、所望のデジタル処理が可能な受光量を表すデジタル値を出力することができる。なお、光電流Ｉｂは、分光特性設定部１２により可視～赤外の分光特性が設定されている間に受光素子ＰＤから発生する光電流であり、光電流Ｉｃは、分光特性設定部１２により赤外の分光特性が設定されている間に受光素子ＰＤから発生する光電流である。 According to the above configuration, the magnitudes of the photocurrents Ib and Ic corresponding to the amount of light received by each light receiving element PD can be converted into digital values (ADCOUTb-α · ADCOUTc) by the analog-digital conversion unit ADC. That is, the optical sensor 1 can output a digital value representing the amount of received light that can be subjected to desired digital processing in illuminance measurement. The photocurrent Ib is a photocurrent generated from the light receiving element PD while the visible to infrared spectral characteristics are set by the spectral characteristic setting unit 12, and the photocurrent Ic is red by the spectral characteristic setting unit 12. This is a photocurrent generated from the light receiving element PD while the external spectral characteristic is set.
　＜アナログ‐デジタル変換部ＡＤＣの変形例＞
　［変形例の構成］
　図１１は、図９および図１０中に示すアナログ‐デジタル変換部ＡＤＣの変形例に係る構成を示す図である。図１１に示すように、アナログ‐デジタル変換部ＡＤＣは、充電回路（積分回路）１５と、放電回路１６と、比較回路１７と、制御回路（出力回路）１８とを備えている。以下では、これらのアナログ‐デジタル変換部ＡＤＣの各構成要素について、詳細に説明する。 <Modification of Analog-to-Digital Converter ADC>
[Configuration of Modification]
FIG. 11 is a diagram illustrating a configuration according to a modification of the analog-digital conversion unit ADC illustrated in FIGS. 9 and 10. As shown in FIG. 11, the analog-digital conversion unit ADC includes a charging circuit (integrating circuit) 15, a discharging circuit 16, a comparison circuit 17, and a control circuit (output circuit) 18. Hereinafter, each component of the analog-digital conversion unit ADC will be described in detail.
　（充電回路１５）
　充電回路１５は、積分器を構成するアンプＡＭＰ１と、コンデンサ（積分コンデンサ）Ｃ１とを備えている。コンデンサＣ１には、入力電流Ｉｉｎに応じた量の電荷が蓄えられる。 (Charging circuit 15)
The charging circuit 15 includes an amplifier AMP1 constituting an integrator and a capacitor (integrating capacitor) C1. An amount of electric charge corresponding to the input current Iin is stored in the capacitor C1.
　（放電回路１６）
　放電回路１６は、電源Ｖｄｄと、コンデンサＣ１に蓄えられた電荷を放電するための基準電流ＩＲＥＦを発生させる基準電流源Ｉｒｅｆと、放電のＯＮ／ＯＦＦを切り替えるためのスイッチＳＷ２とを備えている。 (Discharge circuit 16)
The discharge circuit 16 includes a power supply Vdd, a reference current source Iref that generates a reference current IREF for discharging the charge stored in the capacitor C1, and a switch SW2 for switching ON / OFF of discharge.
　（比較回路１７）
　比較回路１７は、比較器ＣＭＰ１と、スイッチＳＷ１とを備えている。ここで、比較器ＣＭＰ１は、充電回路１５の出力電圧Ｖｓｉｇと、基準電圧源Ｖ１が供給する基準電圧Ｖｒｅｆとを比較して、出力信号（パルス信号）ｃｏｍｐを出力する。 (Comparative circuit 17)
The comparison circuit 17 includes a comparator CMP1 and a switch SW1. Here, the comparator CMP1 compares the output voltage Vsig of the charging circuit 15 with the reference voltage Vref supplied by the reference voltage source V1, and outputs an output signal (pulse signal) comp.
　また、スイッチＳＷ１のＯＮ／ＯＦＦにより、入力電流Ｉｉｎがデジタル値ＡＤＣＯＵＴに変換されるデータ変換期間が決定される。 Also, the data conversion period in which the input current Iin is converted to the digital value ADCOUT is determined by turning on / off the switch SW1.
　まず、スイッチＳＷ１がＯＮされると、基準電圧源Ｖ１が充電回路１５に接続され、コンデンサＣ１に基準電圧Ｖｒｅｆが供給されて、コンデンサＣ１が充電される。また、スイッチＳＷ１がＯＦＦされると、充電回路１５の出力電圧Ｖｓｉｇと基準電圧Ｖｒｅｆとが比較器ＣＭＰ１により比較される。当該比較結果の出力信号ｃｏｍｐは、「Ｈｉｇｈ」と「Ｌｏｗ」との２値のパルス信号として制御回路に入力される。スイッチＳＷ１がＯＦＦされている期間に入力される入力電流Ｉｉｎは、デジタル値ＡＤＣＯＵＴに変換される。 First, when the switch SW1 is turned on, the reference voltage source V1 is connected to the charging circuit 15, the reference voltage Vref is supplied to the capacitor C1, and the capacitor C1 is charged. When the switch SW1 is turned off, the output voltage Vsig of the charging circuit 15 and the reference voltage Vref are compared by the comparator CMP1. The comparison output signal comp is input to the control circuit as a binary pulse signal of “High” and “Low”. An input current Iin that is input while the switch SW1 is OFF is converted to a digital value ADCOUT.
　（制御回路１８）
　制御回路１８は、フリップフロップＦＦと、カウンタＣＯＵＮＴとを備えている。フリップフロップＦＦにより、比較回路１７の出力信号ｃｏｍｐがラッチされる。これにより、ビットストリーム信号ｃｈａｒｇｅは、放電回路１６およびカウンタＣＯＵＮＴにそれぞれ入力される。ここで、カウンタＣＯＵＮＴは、ビットストリーム信号ｃｈａｒｇｅのＬＯＷレベル回数（放電回数）を計数する。すなわち、カウンタＣＯＵＮＴは、アクティブパルスを計数する。また、当該計数結果を、入力電流Ｉｉｎに応じたアナログ‐デジタル変換値であるデジタル値ＡＤＣＯＵＴとして出力する。 (Control circuit 18)
The control circuit 18 includes a flip-flop FF and a counter COUNT. The output signal comp of the comparison circuit 17 is latched by the flip-flop FF. Thereby, the bit stream signal charge is input to the discharge circuit 16 and the counter COUNT, respectively. Here, the counter COUNT counts the number of LOW levels (the number of discharges) of the bit stream signal charge. That is, the counter COUNT counts active pulses. Further, the count result is output as a digital value ADCOUT which is an analog-digital conversion value corresponding to the input current Iin.
　ここで、放電回路１６のスイッチＳＷ２は、ビットストリーム信号ｃｈａｒｇｅに基づいてＯＮ／ＯＦＦされる。まず、放電回路１６のスイッチＳＷ２がＯＮされると、放電回路１６により、充電回路１５のコンデンサＣ１に電荷が蓄えられる。スイッチＳＷ２がＯＦＦされると、入力電流Ｉｉｎに応じて充電回路１５のコンデンサＣ１の電荷が放電される。以下では、上述の構成を備えるアナログ‐デジタル変換部ＡＤＣの動作について説明する。 Here, the switch SW2 of the discharge circuit 16 is turned ON / OFF based on the bit stream signal charge. First, when the switch SW2 of the discharge circuit 16 is turned on, electric charge is stored in the capacitor C1 of the charging circuit 15 by the discharge circuit 16. When the switch SW2 is turned off, the charge of the capacitor C1 of the charging circuit 15 is discharged according to the input current Iin. Below, operation | movement of the analog-digital conversion part ADC provided with the above-mentioned structure is demonstrated.
　［変形例の動作］
　図１２は、図１１に示すアナログ‐デジタル変換部ＡＤＣの動作を示す波形図である。 [Operation of modification]
FIG. 12 is a waveform diagram showing an operation of the analog-digital conversion unit ADC shown in FIG.
　まず、スイッチＳＷ１にＨｉｇｈレベルの信号が入力されると、スイッチＳＷ１はＯＦＦされ、入力電流Ｉｉｎのデジタル値ＡＤＣＯＵＴへの変換が開始される。 First, when a high level signal is input to the switch SW1, the switch SW1 is turned off, and the conversion of the input current Iin into the digital value ADCOUT is started.
　また、スイッチＳＷ２にＨｉｇｈレベルの信号が入力されると、該スイッチＳＷ２はＯＦＦされ、入力電流Ｉｉｎに応じて充電回路１５のコンデンサＣ１に蓄えられた電荷が放電される（プリチャージ動作）。これにより、充電回路１５の出力電圧Ｖｓｉｇは低下していく。最初に充電回路１５の出力電圧Ｖｓｉｇと基準電圧Ｖｒｅｆとが同じように設定されているため、この期間において、充電回路の出力電圧Ｖｓｉｇは基準電圧Ｖｒｅｆを下回る。 Further, when a high level signal is input to the switch SW2, the switch SW2 is turned off, and the charge stored in the capacitor C1 of the charging circuit 15 is discharged according to the input current Iin (precharge operation). As a result, the output voltage Vsig of the charging circuit 15 decreases. First, since the output voltage Vsig of the charging circuit 15 and the reference voltage Vref are set in the same manner, the output voltage Vsig of the charging circuit falls below the reference voltage Vref during this period.
　その後、スイッチＳＷ２にＬｏｗレベルの信号が入力されると、スイッチＳＷ２はＯＮされ、放電回路１６より充電回路１５のコンデンサＣ１に電荷が充電される。これにより、充電回路１５の出力電圧Ｖｓｉｇは増加していく。ある時点で、充電回路１５の出力電圧Ｖｓｉｇは基準電圧Ｖｒｅｆを上回る。充電回路１５の出力電圧Ｖｓｉｇと基準電圧Ｖｒｅｆとは、比較器ＣＭＰ１によって比較され、充電回路１５の出力電圧Ｖｓｉｇが基準電圧Ｖｒｅｆを上回ると、Ｈｉｇｈレベルの出力信号ｃｏｍｐが比較器ＣＭＰ１から出力される。 Thereafter, when a low level signal is input to the switch SW2, the switch SW2 is turned on, and the capacitor C1 of the charging circuit 15 is charged by the discharging circuit 16 with the electric charge. As a result, the output voltage Vsig of the charging circuit 15 increases. At some point, the output voltage Vsig of the charging circuit 15 exceeds the reference voltage Vref. The output voltage Vsig of the charging circuit 15 and the reference voltage Vref are compared by the comparator CMP1, and when the output voltage Vsig of the charging circuit 15 exceeds the reference voltage Vref, a high level output signal comp is output from the comparator CMP1. .
　制御回路１８のフリップフロップＦＦにＨｉｇｈレベルの出力信号ｃｏｍｐが入力されると、フリップフロップＦＦは出力信号ｃｏｍｐをラッチし、次のクロック信号ｃｌｋの立ち上がりに同期して、Ｈｉｇｈレベルのビットストリーム信号ｃｈａｒｇｅを出力する。 When the high-level output signal comp is input to the flip-flop FF of the control circuit 18, the flip-flop FF latches the output signal comp, and in synchronization with the rise of the next clock signal clk, the high-level bit stream signal charge. Is output.
　スイッチＳＷ２にＨｉｇｈレベルのビットストリーム信号ｃｈａｒｇｅが入力されると、スイッチＳＷ２はＯＦＦされ、充電回路１５のコンデンサＣ１に蓄えられた電荷が放電される。これにより、充電回路１５の出力電圧Ｖｓｉｇは低下していく。ある時点で、充電回路１５の出力電圧Ｖｓｉｇは基準電圧Ｖｒｅｆを下回る。充電回路１５の出力電圧Ｖｓｉｇが基準電圧Ｖｒｅｆを下回ると、比較器ＣＭＰ１の出力がアクティブレベルにあることを示すアクティブパルスとしてのＬｏｗレベルの出力信号ｃｏｍｐが出力される。なお、当該アクティブパルスをＬｏｗレベルとＨｉｇｈレベルとのいずれに設定してもよく、回路の動作論理によって適宜選択可能である。 When the high-level bit stream signal charge is input to the switch SW2, the switch SW2 is turned off, and the charge stored in the capacitor C1 of the charging circuit 15 is discharged. As a result, the output voltage Vsig of the charging circuit 15 decreases. At some point, the output voltage Vsig of the charging circuit 15 falls below the reference voltage Vref. When the output voltage Vsig of the charging circuit 15 falls below the reference voltage Vref, a low level output signal comp is output as an active pulse indicating that the output of the comparator CMP1 is at the active level. Note that the active pulse may be set to either the Low level or the High level, and can be appropriately selected depending on the operation logic of the circuit.
　制御回路１８のフリップフロップＦＦにＬｏｗレベルの出力信号ｃｏｍｐが入力されると、該フリップフロップＦＦが出力信号ｃｏｍｐをラッチすることで制御回路１８は出力信号ｃｏｍｐを取り込み、フリップフロップＦＦは次のクロック信号ｃｌｋの立ち上がりに同期して、Ｌｏｗレベルのビットストリーム信号ｃｈａｒｇｅを出力する。 When the low-level output signal comp is input to the flip-flop FF of the control circuit 18, the flip-flop FF latches the output signal comp so that the control circuit 18 takes in the output signal comp, and the flip-flop FF A low-level bit stream signal charge is output in synchronization with the rise of the signal clk.
　スイッチＳＷ２にＬｏｗレベルのビットストリーム信号ｃｈａｒｇｅが入力されると、該スイッチＳＷ２はＯＮされる。ここで、ビットストリーム信号ｃｈａｒｇｅは、Ｌｏｗレベル信号（アクティブパルス）の時系列的並びであり、Ｌｏｗレベル期間（アクティブパルス期間）にスイッチＳＷ２がＯＮされる。 When a low-level bit stream signal charge is input to the switch SW2, the switch SW2 is turned on. Here, the bit stream signal charge is a time-series arrangement of low level signals (active pulses), and the switch SW2 is turned on during the low level period (active pulse period).
　アナログ‐デジタル変換部ＡＤＣは、上記のような動作を繰り返し、スイッチＳＷ１がＯＦＦされている期間、すなわちデータ変換期間ｔ＿ｃｏｎｖに、カウンタＣＯＵＮＴが、放電回路１６の放電回数ｃｏｕｎｔをカウントすることで、入力電流Ｉｉｎに応じたデジタル値ＡＤＣＯＵＴを出力することが可能になる。 The analog-digital conversion unit ADC repeats the above operation, and the counter COUNT counts the number of discharges count of the discharge circuit 16 during the period in which the switch SW1 is turned off, that is, the data conversion period t_conv. It becomes possible to output a digital value ADCOUT corresponding to the current Iin.
　ここで、データ変換期間ｔ＿ｃｏｎｖに入力電流Ｉｉｎにより充電される電荷量は、クロック信号ｃｌｋの周期をｔ＿ｃｌｋとすると、
Ｉｉｎ×ｔ＿ｃｏｎｖ
となり、放電回路１６に流れる基準電流ＩＲＥＦにより一度に放電される電荷量は、
ＩＲＥＦ×ｔ＿ｃｌｋ
となる。充電電荷量Ｉｉｎ×ｔ＿ｃｏｎｖと、データ変換期間ｔ＿ｃｏｎｖに放電される電荷量の合計とが等しくなるので、
Ｉｉｎ×ｔ＿ｃｏｎｖ＝ＩＲＥＦ×ｔ＿ｃｌｋ×ｃｏｕｎｔ　　…（１）
となる。上式（１）により、
ｃｏｕｎｔ＝（Ｉｉｎ×ｔ＿ｃｏｎｖ）／（ＩＲＥＦ×ｔ＿ｃｌｋ）　　…（２）
が導かれる。 Here, the amount of charge charged by the input current Iin in the data conversion period t_conv is, assuming that the period of the clock signal clk is t_clk.
Iin × t_conv
The amount of charge discharged at a time by the reference current IREF flowing through the discharge circuit 16 is
IREF x t_clk
It becomes. Since the charge amount Iin × t_conv is equal to the total amount of charge discharged in the data conversion period t_conv,
Iin × t_conv = IREF × t_clk × count (1)
It becomes. From the above equation (1),
count = (Iin × t_conv) / (IREF × t_clk) (2)
Is guided.
　アナログ‐デジタル変換部ＡＤＣの最小分解能は、（ＩＲＥＦ×ｔ＿ｃｌｋ）で決定されることになる。ここで、最小分解能をｎとすると、充電期間ｔ＿ｃｏｎｖは、
ｔ＿ｃｏｎｖ=ｔ＿ｃｌｋ×２ｎ　　…（３）
に設定されるので、
ｃｏｕｎｔ＝（Ｉｉｎ／ＩＲＥＦ）×２ｎ　　…（４）
が導かれる。 The minimum resolution of the analog-digital conversion unit ADC is determined by (IREF × t_clk). Here, when the minimum resolution is n, the charging period t_conv is
t_conv = t_clk × 2 n (3)
Is set to
count = (Iin / IREF) × 2 n (4)
Is guided.
　例えば、分解能ｎ＝１６ビットの場合、カウンタＣＯＵＮＴは、入力電流Ｉｉｎに応じた値を、０～６５５３５の範囲で出力することになる。これにより、積分型アナログ‐デジタル変換部ＡＤＣは、広いダイナミックレンジと高い分解能のアナログ‐デジタル変換が可能である。また、このような積分型アナログ‐デジタル変換部ＡＤＣは、照度センサや近接センサに好適である。 For example, when the resolution n = 16 bits, the counter COUNT outputs a value corresponding to the input current Iin in the range of 0 to 65535. As a result, the integration type analog-to-digital conversion unit ADC can perform analog-to-digital conversion with a wide dynamic range and high resolution. Further, such an integral type analog-digital conversion unit ADC is suitable for an illuminance sensor or a proximity sensor.
　上記のように、アナログ‐デジタル変換部ＡＤＣにより、上述の各センサから出力される電流を入力電流Ｉｉｎとして、アナログ‐デジタル変換しデジタル値を利用する事で、安価な構成で精度の高い色温度または照度を算出することができる。 As described above, the analog-to-digital conversion unit ADC uses the current output from each of the above-described sensors as the input current Iin and performs analog-to-digital conversion and uses a digital value, thereby providing a highly accurate color temperature with an inexpensive configuration. Alternatively, the illuminance can be calculated.
　また、図１１に示すアナログ‐デジタル変換部ＡＤＣでは、アンプＡＭＰ１の非反転入力端子への入力電圧を０Ｖに設定することができる。これにより、上述のＰＮ接合（ＰＤｉｒ、ＰＤｖｉｓ）の両端電圧（バイアス電圧）を０Ｖとすることが可能である。よって、ＰＮ接合の暗電流を低減することが可能であり、低い光量まで正確に測定することが可能である。つまり、低感度での測定を正確に行うことができる。 In the analog-digital conversion unit ADC shown in FIG. 11, the input voltage to the non-inverting input terminal of the amplifier AMP1 can be set to 0V. Thereby, the both-ends voltage (bias voltage) of the above-mentioned PN junction (PDir, PDvis) can be set to 0V. Therefore, it is possible to reduce the dark current of the PN junction, and it is possible to accurately measure even a low light amount. That is, measurement with low sensitivity can be performed accurately.
　［変形例の効果］
　上記構成によれば、光センサ１は、所望のデジタル処理が可能な受光量を表すデジタル値を出力することができる。また、光センサ１は、正確に低感度での受光量を測定することができる。 [Effect of modification]
According to the above configuration, the optical sensor 1 can output a digital value representing the amount of received light that can be subjected to desired digital processing. Further, the optical sensor 1 can accurately measure the amount of received light with low sensitivity.
　＜アナログ‐デジタル変換部ＡＤＣの利用例＞
　図１３は、図９～図１１中に示すアナログ‐デジタル変換部ＡＤＣが近接検知において出力するデジタル信号などの波形図であり、（ａ）は物体の近接を検知した場合を示し、（ｂ）は物体の非近接を検知した場合を示す図である。なお、光センサ１の構成は、図３に示す構成と同様である。ここで、発光素子ＬＥＤを駆動している期間のデジタル信号ＤＯＵＴをＤａｔａ１として、発光素子ＬＥＤを駆動していない期間のデジタル信号ＤＯＵＴをＤａｔａ２とすると、それらのデータの差分（Ｄａｔａ１－Ｄａｔａ２）が近接データとなる。 <Usage example of analog-digital converter ADC>
FIG. 13 is a waveform diagram of digital signals and the like output in proximity detection by the analog-to-digital conversion unit ADC shown in FIGS. 9 to 11, and (a) shows a case where the proximity of an object is detected, and (b) FIG. 5 is a diagram illustrating a case where non-adjacent objects are detected. The configuration of the optical sensor 1 is the same as the configuration shown in FIG. Here, if the digital signal DOUT during the period when the light emitting element LED is driven is Data1, and the digital signal DOUT during the period when the light emitting element LED is not driven is Data2, the difference between the data (Data1-Data2) is close. It becomes data.
　図１３の（ａ）に示すように、近接検知物体があるときに発光素子ＬＥＤが駆動されると、近接検知物体からの反射光が強くなるため、受光素子ＰＤに流れる電流は大きくなる。これにより、近接データ（Ｄａｔａ１－Ｄａｔａ２）は制御回路の閾値Ｄａｔａ＿ｔｈを越えるため、近接と判断される。 As shown in FIG. 13A, when the light emitting element LED is driven when there is a proximity detection object, the reflected light from the proximity detection object becomes strong, so that the current flowing through the light receiving element PD increases. As a result, the proximity data (Data 1 -Data 2) exceeds the threshold Data_th of the control circuit, and thus is determined to be close.
　一方、図１３の（ｂ）に示すように、近接検知物体がない場合、発光素子ＬＥＤが駆動されていても、受光素子ＰＤへの入射光が弱いため、受光素子ＰＤに流れる電流は小さい。そのため、近接データ（Ｄａｔａ１－Ｄａｔａ２）は制御回路の閾値Ｄａｔａ＿ｔｈを越えないので、非近接と判断される。 On the other hand, as shown in FIG. 13B, when there is no proximity detection object, even if the light emitting element LED is driven, the incident light to the light receiving element PD is weak, so the current flowing through the light receiving element PD is small. For this reason, the proximity data (Data 1 -Data 2) does not exceed the threshold Data_th of the control circuit, and is thus determined as non-proximity.
　〔実施形態３〕
　本発明の他の実施形態について、図１４に基づいて説明すれば、以下のとおりである。なお、説明の便宜上、上述の実施形態にて説明した部材と同じ機能を有する部材については、同じ符号を付記し、その説明を省略する。 [Embodiment 3]
The following will describe another embodiment of the present invention with reference to FIG. For convenience of explanation, members having the same functions as those described in the above-described embodiment are denoted by the same reference numerals and description thereof is omitted.
　＜表示装置５の構成、動作、および効果＞
　図１４は、本発明の他の実施形態に係る表示装置５の概略構成を示すブロック図である。表示装置５は、光センサ１と、バックライト制御部５１と、バックライト５２と、液晶パネル５５とを備えている。 <Configuration, operation, and effect of display device 5>
FIG. 14 is a block diagram showing a schematic configuration of a display device 5 according to another embodiment of the present invention. The display device 5 includes the optical sensor 1, a backlight control unit 51, a backlight 52, and a liquid crystal panel 55.
　バックライト５２は、画面を表示する液晶パネル５５の背面から光を照射するための光源であり、例えば、赤色ＬＥＤ、緑色ＬＥＤ、および青色ＬＥＤを有している。光センサ１は、表示装置５の周囲光を受光して周囲光の色成分を測定し、測定結果としてデジタル信号ＤＯＵＴをバックライト制御部５１に出力する。バックライト制御部５１は、デジタル信号ＤＯＵＴから演算して色成分や照度を算出する。そして、当該算出された情報を基に、バックライト５２の赤色ＬＥＤ、緑色ＬＥＤ、および青色ＬＥＤの各輝度を制御することにより、上記周囲光の色成分に応じてバックライト５２の色彩を制御または輝度を制御することができる。 The backlight 52 is a light source for irradiating light from the back surface of the liquid crystal panel 55 that displays a screen, and has, for example, a red LED, a green LED, and a blue LED. The optical sensor 1 receives the ambient light of the display device 5 and measures the color component of the ambient light, and outputs a digital signal DOUT to the backlight control unit 51 as a measurement result. The backlight control unit 51 calculates a color component and illuminance by calculating from the digital signal DOUT. Based on the calculated information, the brightness of the red LED, green LED, and blue LED of the backlight 52 is controlled to control the color of the backlight 52 according to the color component of the ambient light or The brightness can be controlled.
　例えば、周囲光の照度が大きい場合、バックライト制御部５１はバックライト５２の輝度を上げるように制御し、周囲光の照度が小さい場合、バックライト制御部５１はバックライト５２の輝度を下げるように制御する。これにより、バックライト５２の消費電力を抑えることができるとともに、目の色順応に対応するように液晶パネル５５の色味を正確に制御することができる。 For example, when the illuminance of the ambient light is large, the backlight control unit 51 controls to increase the luminance of the backlight 52, and when the illuminance of the ambient light is small, the backlight control unit 51 decreases the luminance of the backlight 52. To control. Thereby, the power consumption of the backlight 52 can be suppressed, and the color of the liquid crystal panel 55 can be accurately controlled so as to correspond to the color adaptation of the eyes.
　また、表示装置５は、光センサ１により周囲の物体の近接を正確に検知できるので、周囲の物体の近接に応じて、バックライト５２の輝度制御をすることができる。このような表示装置５は、例えば、液晶パネル５５のような表示パネルを備えた携帯電話やデジタルスチルカメラに好適である。 In addition, since the display device 5 can accurately detect the proximity of the surrounding object by the optical sensor 1, the brightness of the backlight 52 can be controlled according to the proximity of the surrounding object. Such a display device 5 is suitable for a mobile phone or a digital still camera including a display panel such as the liquid crystal panel 55, for example.
　なお、光センサ１から出力される信号は、上述のアナログ‐デジタル変換部ＡＤＣにより変換されても良く、この場合には、バックライト制御部５１は、当該変換された出力信号に基づいて、バックライト５２の輝度を制御してもよい。 Note that the signal output from the optical sensor 1 may be converted by the above-described analog-digital conversion unit ADC. In this case, the backlight control unit 51 performs the backlight based on the converted output signal. The brightness of the light 52 may be controlled.
　また、表示装置５は、他の製品に適用して、応用製品（携帯電話、デジタルカメラ）６の一部として、利用されてもよい。 Further, the display device 5 may be applied to other products and used as a part of an application product (mobile phone, digital camera) 6.
　〔ソフトウェアによる実現例〕
　光センサ１の制御ブロック（特に制御部１０、１０ａ、１０ｂ）は、集積回路（ＩＣチップ）等に形成された論理回路（ハードウェア）によって実現してもよいし、ＣＰＵ（Central Processing Unit）を用いてソフトウェアによって実現してもよい。 [Example of software implementation]
The control block (especially the control units 10, 10a, 10b) of the optical sensor 1 may be realized by a logic circuit (hardware) formed in an integrated circuit (IC chip) or the like, or a CPU (Central Processing Unit). And may be realized by software.
　後者の場合、制御部１０、１０ａ、１０ｂは、各機能を実現するソフトウェアであるプログラムの命令を実行するＣＰＵ、上記プログラムおよび各種データがコンピュータ（またはＣＰＵ）で読み取り可能に記録されたＲＯＭ（Read Only Memory）または記憶装置（これらを「記録媒体」と称する）、上記プログラムを展開するＲＡＭ（Random Access Memory）などを備えている。そして、コンピュータ（またはＣＰＵ）が上記プログラムを上記記録媒体から読み取って実行することにより、本発明の目的が達成される。上記記録媒体としては、「一時的でない有形の媒体」、例えば、テープ、ディスク、カード、半導体メモリ、プログラマブルな論理回路などを用いることができる。また、上記プログラムは、該プログラムを伝送可能な任意の伝送媒体（通信ネットワークや放送波等）を介して上記コンピュータに供給されてもよい。なお、本発明は、上記プログラムが電子的な伝送によって具現化された、搬送波に埋め込まれたデータ信号の形態でも実現され得る。 In the latter case, the control units 10, 10 a, and 10 b include a CPU that executes instructions of a program that is software that realizes each function, and a ROM (Read that records the above program and various data so that the computer (or CPU) can read them. Only Memory) or a storage device (these are referred to as “recording media”), RAM (Random Access Memory) for expanding the program, and the like. And the objective of this invention is achieved when a computer (or CPU) reads the said program from the said recording medium and runs it. As the recording medium, a “non-temporary tangible medium” such as a tape, a disk, a card, a semiconductor memory, a programmable logic circuit, or the like can be used. The program may be supplied to the computer via an arbitrary transmission medium (such as a communication network or a broadcast wave) that can transmit the program. The present invention can also be realized in the form of a data signal embedded in a carrier wave in which the program is embodied by electronic transmission.
　〔まとめ〕
　本発明の態様１に係る光センサ１は、基板２１を有し、受光量を測定する光センサであって、上記基板上に配された、受光して光電流を発生させる複数の受光素子（受光素子群ＰＤＧ）と、上記複数の受光素子のうち、一部の受光素子を選択する受光素子選択手段（受光素子選択部１１）と、上記複数の受光素子の分光特性をそれぞれ設定する分光特性設定手段（分光特性設定部１２）と、上記受光素子選択手段により選択され、かつ、上記分光特性設定手段により分光特性が設定された受光素子から発生した光電流を待ち受け、上記受光量を計算する受光量計算手段（受光量計算部１３）とを備えている。 [Summary]
The optical sensor 1 according to the first aspect of the present invention is an optical sensor that has a substrate 21 and measures the amount of received light, and is a plurality of light receiving elements (on the substrate) that receive light and generate a photocurrent. Light receiving element group PDG), light receiving element selecting means (light receiving element selecting unit 11) for selecting some of the plurality of light receiving elements, and spectral characteristics for setting the spectral characteristics of the plurality of light receiving elements, respectively. The photocurrent generated from the light receiving element selected by the setting means (spectral characteristic setting unit 12) and the light receiving element selecting means and having the spectral characteristic set by the spectral characteristic setting means is waited, and the amount of received light is calculated. And a received light amount calculation means (received light amount calculator 13).
　また、本発明の態様１１に係る受光量の測定方法は、基板２１と、上記基板上に配された、受光して光電流を発生させる複数の受光素子（受光素子群ＰＤＧ）とを備えた光センサ１を利用した受光量の測定方法であって、上記複数の受光素子のうち、一部の受光素子を選択する受光素子選択工程と、上記複数の受光素子の分光特性をそれぞれ設定する分光特性設定工程と、上記受光素子選択工程において選択され、かつ、上記分光特性設定工程において分光特性が設定された受光素子から発生した光電流を待ち受け、上記受光量を計算する受光量計算工程とを含んでいる。 In addition, the method for measuring the amount of received light according to the eleventh aspect of the present invention includes the substrate 21 and a plurality of light receiving elements (light receiving element group PDG) arranged on the substrate to receive light and generate a photocurrent. A method for measuring the amount of received light using the optical sensor 1, wherein a light receiving element selection step for selecting a part of the plurality of light receiving elements and a spectral characteristic for setting the spectral characteristics of the plurality of light receiving elements, respectively. A characteristic setting step, and a received light amount calculating step of waiting for a photocurrent generated from the light receiving element selected in the light receiving element selecting step and having the spectral characteristics set in the spectral characteristic setting step, and calculating the received light amount. Contains.
　上記構成によれば、受光素子選択手段によって、複数の受光素子のうち基板上の特定の位置に配された受光素子が選択され、かつ、分光特性設定手段によって、特定の波長の光を受光した場合に、他の波長の光を受光した場合よりも大きな光電流を発生させるように、受光素子の分光特性が設定される。これにより、受光量計算手段は、基板上の特定の位置に入射する光であって、特定の波長の光の光量に応じた光電流を、受光素子から受けることができる。 According to the above configuration, a light receiving element arranged at a specific position on the substrate is selected by the light receiving element selecting unit, and light having a specific wavelength is received by the spectral characteristic setting unit. In this case, the spectral characteristic of the light receiving element is set so that a larger photocurrent is generated than when light of other wavelengths is received. Thereby, the received light amount calculation means can receive a photocurrent corresponding to the light amount of light having a specific wavelength, which is light incident on a specific position on the substrate, from the light receiving element.
　ここで、上述の特定の位置と、特定の波長とは任意に選択されてもよい。よって、受光量計算手段は、外乱となる位置に入射する光や、外乱となる波長の光の悪影響を抑制して、光センサの受光量を計算できる。 Here, the specific position and the specific wavelength described above may be arbitrarily selected. Therefore, the received light amount calculation means can calculate the received light amount of the photosensor while suppressing the adverse effect of the light incident on the position that causes the disturbance or the light having the wavelength that causes the disturbance.
　また、このような光センサは、光センサに近接する物体を検知する近接検知や、光センサが置かれた環境の照度を測定する照度測定に利用できる。 Also, such an optical sensor can be used for proximity detection for detecting an object close to the optical sensor and for illuminance measurement for measuring the illuminance of the environment where the optical sensor is placed.
　すなわち、このような光センサや該光センサを利用した受光量の測定方法により、近接検知や照度測定において、外乱となる光に起因する悪影響を抑制することができる。 That is, by using such an optical sensor and a method of measuring the amount of received light using the optical sensor, adverse effects caused by disturbing light can be suppressed in proximity detection and illuminance measurement.
　なお、「受光素子の分光特性」とは、一定光量の光の波長と、受光素子が該光を受光し発生させる光電流の大きさとの関係を意味する。 The “spectral characteristic of the light receiving element” means the relationship between the wavelength of light having a certain amount of light and the magnitude of the photocurrent generated by the light receiving element receiving the light.
　また、「受光素子の分光特性を設定する」とは、所定の範囲に含まれる波長に対して、受光素子が該波長かつ一定光量の光を受光し発生させる光電流の大きさを設定することを意味する。 “Setting the spectral characteristics of the light receiving element” means setting the magnitude of the photocurrent that the light receiving element receives and generates a certain amount of light with respect to a wavelength included in a predetermined range. Means.
　本発明の態様２に係る光センサ１は、上記態様１において、少なくとも赤外光を出射する発光素子ＬＥＤをさらに備え、上記受光素子選択手段は、上記複数の受光素子のうち、上記基板上の上記複数の受光素子が配された領域Ｄの上記発光素子側に配された一部の受光素子（ＰＤ１３、１４、２３、２４、３３、３４、４３、４４）を選択し、上記分光特性設定手段は、上記受光素子選択手段により選択された受光素子の分光特性として、赤外の分光特性を設定してもよい。 The optical sensor 1 according to aspect 2 of the present invention further includes a light emitting element LED that emits at least infrared light in the above aspect 1, and the light receiving element selection unit includes the light receiving element on the substrate among the plurality of light receiving elements. Select a part of the light receiving elements (PD13, 14, 23, 24, 33, 34, 43, 44) arranged on the light emitting element side of the region D where the plurality of light receiving elements are arranged, and set the spectral characteristics The means may set an infrared spectral characteristic as the spectral characteristic of the light receiving element selected by the light receiving element selecting means.
　光センサは、発光素子から出射された光を物体に反射させ、反射光を受光素子で受光することにより、物体が近接していることを検知する。このような光センサは、例えば携帯端末などの筐体の内部に組み込まれ利用されることがある。 The light sensor reflects the light emitted from the light emitting element to the object and receives the reflected light by the light receiving element, thereby detecting that the object is close. Such an optical sensor may be used by being incorporated in a housing such as a portable terminal.
　ここで、発光素子から出射され筐体で反射された筐体反射光が受光素子に入射し、受光素子は、発光素子から出射され筐体外部の物体で反射された物体反射光が該受光素子に入射した場合に発生する光電流と同様の光電流を発生させることがある。この場合、光センサは、筐体反射光と物体反射光とを判別できず、該物体が光センサに近接していなくても近接していると誤検知する。 Here, the case reflected light emitted from the light emitting element and reflected by the casing enters the light receiving element, and the light receiving element receives the object reflected light emitted from the light emitting element and reflected by an object outside the casing. In some cases, a photocurrent similar to the photocurrent generated when the light enters the light source is generated. In this case, the optical sensor cannot distinguish between the case reflected light and the object reflected light, and erroneously detects that the object is close even if it is not close to the optical sensor.
　上記構成によれば、受光素子選択手段が、複数の受光素子のうち、基板上の複数の受光素子が配された領域の発光素子側に配された一部の受光素子、つまり他の受光素子と比較して筐体反射光が入射する可能性が低い受光素子を選択するため、受光量計算手段は、受光量の計算において、筐体反射光の影響を抑制できる。換言するならば、光センサは、受光領域に配された複数の受光素子のうち、一部の受光素子を選択することで、物体反射光を積極的に受光するように光学特性を調整し、受光量の測定においてノイズとなる筐体反射光の受光量を低減することができる。 According to the above configuration, the light receiving element selection unit includes a part of the plurality of light receiving elements disposed on the light emitting element side of the region where the plurality of light receiving elements are disposed on the substrate, that is, another light receiving element Therefore, the light receiving amount calculation unit can suppress the influence of the case reflected light in the calculation of the amount of received light. In other words, the optical sensor adjusts the optical characteristics so as to positively receive object reflected light by selecting some of the light receiving elements arranged in the light receiving region, It is possible to reduce the received light amount of the case reflected light that becomes noise in the measurement of the received light amount.
　また、例えば蛍光灯などから出射された可視光が受光素子に入射した場合でも、分光特性設定手段は、受光素子選択手段により選択された受光素子の分光特性として、赤外の分光特性を設定するので、該受光素子は、可視光に起因する光電流の発生を抑制し、発光素子から出射された赤外光を選択的に受光して光電流を発生させる。よって、受光量計算手段は、受光量の計算において、可視光の影響を抑制できる。このように、光センサは、可視光に起因する誤検知を抑制できるため、近接検知に適している。 Further, for example, even when visible light emitted from a fluorescent lamp or the like enters the light receiving element, the spectral characteristic setting unit sets the infrared spectral characteristic as the spectral characteristic of the light receiving element selected by the light receiving element selecting unit. Therefore, the light receiving element suppresses generation of a photocurrent caused by visible light, and selectively receives infrared light emitted from the light emitting element to generate a photocurrent. Therefore, the received light amount calculation means can suppress the influence of visible light in calculating the received light amount. In this way, the optical sensor is suitable for proximity detection because it can suppress erroneous detection due to visible light.
　すなわち、光センサは、筐体反射光に起因する悪影響を抑制可能であるとともに、近接検知に好適である。 That is, the optical sensor can suppress adverse effects caused by the reflected light from the housing and is suitable for proximity detection.
　なお、「赤外の分光特性」とは、受光素子が一定光量の赤外光を受光し発生させる光電流の大きさが、受光素子が該一定光量の光であって赤外光ではない光を受光し発生させる光電流の大きさよりも大きくなるような、受光素子が受光する光の波長と、発生させる光電流の大きさとの関係を意味する。 The “infrared spectral characteristics” means that the magnitude of the photocurrent generated when the light receiving element receives a fixed amount of infrared light is light that the light receiving element is not the infrared light. The relationship between the wavelength of light received by the light receiving element and the magnitude of the photocurrent to be generated, which is larger than the magnitude of the photocurrent that is received and generated.
　本発明の態様３に係る光センサ１では、上記態様１または２において、上記受光素子選択手段は、上記複数の受光素子のうち、上記基板上の上記複数の受光素子が配された領域Ｄの中心付近に配された一部の受光素子（ＰＤ２２、２３、３２、３３）を選択し、上記分光特性設定手段は、該受光素子選択手段により選択された受光素子の分光特性として、可視～赤外の分光特性と、赤外の分光特性とのいずれかを選択し、上記受光量計算手段は、上記分光特性設定手段により可視～赤外の分光特性が設定されている間に該受光素子から発生する光電流の大きさから、上記分光特性設定手段により赤外の分光特性が設定されている間に該受光素子から発生する光電流の大きさを減算して、上記受光量を計算してもよい。 In the optical sensor 1 according to Aspect 3 of the present invention, in the Aspect 1 or 2, the light receiving element selection unit is configured such that, among the plurality of light receiving elements, the region D in which the plurality of light receiving elements on the substrate are arranged. A part of the light receiving elements (PD22, 23, 32, 33) arranged in the vicinity of the center is selected, and the spectral characteristic setting means has visible to red as the spectral characteristics of the light receiving elements selected by the light receiving element selecting means. Either the spectral characteristic of the outside or the spectral characteristic of infrared is selected, and the received light amount calculating means is configured to receive from the light receiving element while the visible to infrared spectral characteristics are set by the spectral characteristic setting means. Calculate the amount of received light by subtracting the magnitude of the photocurrent generated from the light receiving element while the infrared spectral characteristics are set by the spectral characteristic setting means from the magnitude of the generated photocurrent. Also good.
　通常、複数の受光素子が配された領域（受光領域）へ、光センサの外部から入射する光（環境光）の強度分布の重心（入射中心）と、受光領域の中心（受光中心）とが一致するように、光センサは設計される。しかし、光センサに作用する外力や経年劣化などにより、各中心がずれることがある。このため、光センサは、設計された通りに、光センサが置かれた環境の照度を測定できないことがある。 Normally, the center of gravity (incident center) of the intensity distribution of light (environmental light) incident from the outside of the optical sensor and the center of the light receiving area (light receiving center) into the area where the plurality of light receiving elements are arranged (light receiving area) The optical sensor is designed to match. However, each center may be shifted due to external force acting on the optical sensor or aging deterioration. For this reason, the optical sensor may not be able to measure the illuminance of the environment where the optical sensor is placed as designed.
　ここで、各中心がずれる場合、入射中心が受光中心からランダムな方向へ移動した位置へずれると予想されるため、期待される入射中心は、受光中心に一致する。 Here, when each center is deviated, since the incident center is expected to shift to a position moved in a random direction from the light receiving center, the expected incident center coincides with the light receiving center.
　上記構成によれば、受光素子選択手段によって、複数の受光素子のうち、基板上の複数の受光素子が配された領域の中心付近に配された一部の受光素子、つまり他の受光素子と比較して環境光が入射する可能性が高い受光素子が選択されることにより、受光量計算手段は、受光量の計算において、入射中心のずれの影響を抑制できる。換言するならば、光センサは、受光領域に配された複数の受光素子のうち、一部の受光素子を選択することで、環境光を積極的に受光するように光学特性を調整し、受光した光の受光量に対して光センサが実際に測定結果として出力する該光の受光量を表す感度のばらつきを少なくすることができる。 According to the above configuration, among the plurality of light receiving elements, a part of the light receiving elements disposed near the center of the region where the plurality of light receiving elements are disposed, that is, other light receiving elements By selecting a light receiving element that is more likely to receive ambient light, the received light amount calculation means can suppress the influence of the deviation of the incident center in the calculation of the received light amount. In other words, the optical sensor adjusts the optical characteristics so as to actively receive ambient light by selecting some of the light receiving elements arranged in the light receiving region, and receives the light. It is possible to reduce variation in sensitivity representing the amount of received light that is actually output as a measurement result by the optical sensor with respect to the amount of received light.
　また、分光特性設定手段が、受光素子の分光特性として、可視～赤外の分光特性を設定している間、該受光素子は、可視～赤外光の受光量に応じた光電流を発生させる。また、分光特性設定手段が、該受光素子の分光特性として、赤外の分光特性を設定している間、該受光素子は、赤外光の受光量に応じた光電流を発生させる。 In addition, while the spectral characteristic setting unit sets the visible to infrared spectral characteristic as the spectral characteristic of the light receiving element, the light receiving element generates a photocurrent corresponding to the amount of received visible to infrared light. . Further, while the spectral characteristic setting means sets the infrared spectral characteristic as the spectral characteristic of the light receiving element, the light receiving element generates a photocurrent corresponding to the amount of received infrared light.
　そして、受光量計算手段は、可視～赤外光の受光量に応じた光電流の大きさから、赤外光の受光量に応じた光電流の大きさを減算することで、可視光の受光量に応じた光電流の大きさを計算できる。このように、光センサは、視感度に近い分光特性を実現できるため、照度測定に適している。 The received light amount calculation means subtracts the magnitude of the photocurrent according to the amount of received infrared light from the magnitude of the photocurrent according to the amount of received visible to infrared light, thereby receiving visible light. The magnitude of the photocurrent according to the quantity can be calculated. Thus, the optical sensor is suitable for illuminance measurement because it can realize spectral characteristics close to the visibility.
　すなわち、光センサは、環境光の入射中心のずれに起因する悪影響を抑制可能であるとともに、照度測定に好適である。 That is, the optical sensor can suppress adverse effects caused by the deviation of the incident center of the ambient light and is suitable for illuminance measurement.
　なお、「可視～赤外の分光特性」とは、受光素子が一定光量の可視～赤外光を受光し発生させる光電流の大きさが、受光素子が該一定光量の光であって可視～赤外光ではない光を受光し発生させる光電流の大きさよりも大きくなるような、受光素子が受光する光の波長と、発生させる光電流の大きさとの関係を意味する。 Note that the “visible to infrared spectral characteristics” means that the magnitude of the photocurrent generated when the light receiving element receives visible to infrared light with a certain amount of light is visible when the light receiving element is the light with the certain amount of light. It means the relationship between the wavelength of light received by the light receiving element and the magnitude of the photocurrent to be generated, which is larger than the magnitude of the photocurrent that is received and generated by light that is not infrared light.
　また、「可視～赤外光」とは、可視光または赤外光に含まれる光を意味する。 Further, “visible to infrared light” means light included in visible light or infrared light.
　また、「視感度」とは、所定の範囲に含まれる波長に対して、人の眼が該波長の光を受光した場合に、該人が視覚に感じる明るさの度合いを意味する。ここで、視感度は、可視光の波長の範囲（約４００～７００ｎｍ）の中央付近の波長に対して最大値をとり、該範囲の両端により近い波長に対してより小さい値をとる。 “Visibility” means the degree of brightness that a person's eyes perceive when light of the wavelength is received by a person's eyes with respect to wavelengths within a predetermined range. Here, the visual sensitivity takes a maximum value for the wavelength near the center of the visible light wavelength range (about 400 to 700 nm), and takes a smaller value for wavelengths closer to both ends of the range.
　また、「視感度に近い分光特性」とは、人の眼が受光する光の波長と、該人が視覚に感じる明るさの度合いとの関係に、分光特性が近いことを意味する。 Also, “spectral characteristics close to visual sensitivity” means that the spectral characteristics are close to the relationship between the wavelength of light received by the human eye and the degree of brightness that the person perceives visually.
　本発明の態様４に係る光センサ１では、上記態様１から３のいずれか１態様において、各受光素子は、赤外の分光特性を有する赤外光受光用ＰＮ接合ＰＤｉｒを備えていてもよい。 In the optical sensor 1 according to the aspect 4 of the present invention, in any one of the aspects 1 to 3, each light receiving element may include an infrared light receiving PN junction PDir having infrared spectral characteristics. .
　上記構成によれば、赤外光受光用ＰＮ接合が、受光素子により受光された光に含まれる赤外光の光量に応じた光電流を発生させるため、受光量計算手段は、赤外光の光量に応じた光電流を、受光素子から受けることができる。 According to the above configuration, since the PN junction for receiving infrared light generates a photocurrent corresponding to the amount of infrared light included in the light received by the light receiving element, the received light amount calculating means A photocurrent corresponding to the amount of light can be received from the light receiving element.
　すなわち、光センサは、近接検知や照度測定において、外乱となる赤外光に起因する悪影響を抑制することができる。 That is, the optical sensor can suppress adverse effects caused by infrared light that becomes a disturbance in proximity detection and illuminance measurement.
　本発明の態様５に係る光センサ１では、上記態様１から４のいずれか１態様において、各受光素子は、可視の分光特性を有する可視光受光用ＰＮ接合ＰＤｖｉｓを備えていてもよい。 In the optical sensor 1 according to the fifth aspect of the present invention, in any one of the first to fourth aspects, each light receiving element may include a visible light receiving PN junction PDvis having visible spectral characteristics.
　上記構成によれば、可視光受光用ＰＮ接合が、受光素子により受光された光に含まれる可視光の光量に応じた光電流を発生させるため、受光量計算手段は、可視光の光量に応じた光電流を、受光素子から受けることができる。 According to the above configuration, the PN junction for receiving visible light generates a photocurrent corresponding to the amount of visible light contained in the light received by the light receiving element, so that the received light amount calculation means corresponds to the amount of visible light. The received photocurrent can be received from the light receiving element.
　すなわち、光センサは、近接検知や照度測定において、外乱となる可視光に起因する悪影響を抑制することができる。 That is, the optical sensor can suppress an adverse effect caused by visible light that is a disturbance in proximity detection and illuminance measurement.
　なお、「可視の分光特性」とは、受光素子が一定光量の可視光を受光し発生させる光電流の大きさが、受光素子が該一定光量の光であって可視光ではない光を受光し発生させる光電流の大きさよりも大きくなるような、受光素子が受光する光の波長と光電流の大きさとの関係を意味する。 “Visible spectral characteristics” refers to the magnitude of the photocurrent generated when a light receiving element receives a certain amount of visible light, and the light receiving element receives light that is a certain amount of light but not visible light. It means the relationship between the wavelength of light received by the light receiving element and the magnitude of the photocurrent, which is larger than the magnitude of the photocurrent to be generated.
　本発明の態様６に係る光センサ１では、上記態様１から５のいずれか１態様において、各受光素子は、互いに異なる分光特性を有する３つ以上のＰＮ接合を備えていてもよい。 In the optical sensor 1 according to aspect 6 of the present invention, in any one aspect of the above aspects 1 to 5, each light receiving element may include three or more PN junctions having different spectral characteristics.
　上記構成によれば、３つ以上のＰＮ接合が、受光素子により受光された光に含まれる光であって互いに異なる波長を有する３種以上の光の光量に応じた光電流を発生させるため、受光量計算手段は、３種以上の光の光量に応じた光電流を、受光素子から受けることができる。 According to the above configuration, the three or more PN junctions generate light currents corresponding to the light amounts of three or more types of light that are included in the light received by the light receiving element and have different wavelengths. The received light amount calculation means can receive a photocurrent corresponding to the amount of light of three or more types from the light receiving element.
　すなわち、光センサは、近接検知や照度測定において、外乱となる多様な光に起因する悪影響を抑制することができる。 That is, the optical sensor can suppress adverse effects caused by various kinds of light as disturbances in proximity detection and illuminance measurement.
　本発明の態様７に係る光センサ１は、上記態様１から６のいずれか１態様において、上記複数の受光素子を封止する樹脂封止部２２をさらに備え、上記樹脂封止部は、上記基板上の上記複数の受光素子が配された領域に光を集光するレンズ形状（レンズ２３）を有していてもよい。 The optical sensor 1 according to Aspect 7 of the present invention further includes a resin sealing portion 22 that seals the plurality of light receiving elements in any one of the Aspects 1 to 6, and the resin sealing portion includes the above-described resin sealing portion. You may have the lens shape (lens 23) which condenses light in the area | region where the said several light receiving element was distribute | arranged on the board | substrate.
　光センサが小型化され受光領域が狭くなった場合には、例えばレンズなどにより、光センサが受光する光を狭い領域に集光するといったことが行われる。また、レンズにより、受光する光を狭い領域に集光する場合には、レンズの焦点を当該領域に一致させるといったことが行われる。このような場合には、レンズと光が集光される領域との相対的な位置関係が固定されていることが好ましい。 When the light sensor is downsized and the light receiving area becomes narrow, for example, the light received by the light sensor is condensed in a narrow area by a lens or the like. In addition, when the light received by the lens is collected in a narrow area, the focal point of the lens is matched with the area. In such a case, it is preferable that the relative positional relationship between the lens and the region where the light is collected is fixed.
　上記構成によれば、光センサが受光する光が、レンズ形状により受光領域に集光されるとともに、レンズ形状と受光領域との相対的な位置関係が固定されるので、受光領域が狭くなった場合であっても、受光素子は正確に光を受光することができる。 According to the above configuration, the light received by the optical sensor is focused on the light receiving region by the lens shape, and the relative positional relationship between the lens shape and the light receiving region is fixed, so the light receiving region is narrowed. Even in this case, the light receiving element can accurately receive light.
　本発明の態様８に係る光センサ１は、上記態様１から７のいずれか１態様において、上記光電流の大きさをデジタル値に変換するアナログ‐デジタル変換手段（アナログ‐デジタル変換部ＡＤＣ）をさらに備えていてもよい。 The optical sensor 1 according to aspect 8 of the present invention is the optical sensor 1 according to any one of the aspects 1 to 7, wherein analog-digital conversion means (analog-digital conversion unit ADC) for converting the magnitude of the photocurrent into a digital value is provided. Furthermore, you may provide.
　上記構成によれば、アナログ‐デジタル変換手段により、受光素子の受光量に応じた光電流の大きさをデジタル値に変換できる。すなわち、光センサは、所望のデジタル処理が可能な受光量を表すデジタル値を出力することができる。 According to the above configuration, the magnitude of the photocurrent corresponding to the amount of light received by the light receiving element can be converted into a digital value by the analog-digital conversion means. That is, the optical sensor can output a digital value representing the amount of received light that can be subjected to desired digital processing.
　本発明の態様９に係る光センサ１は、上記態様１から７のいずれか１態様において、上記光電流の大きさに応じた電荷を蓄える積分コンデンサ（コンデンサＣ１）を備え、該積分コンデンサが蓄える電荷量に対応する電圧を出力する積分回路（充電回路１５）と、上記積分回路の出力電圧Ｖｓｉｇと基準電圧Ｖｒｅｆとの互いの高低を比較して、その比較結果を２値のパルス信号（出力信号ｃｏｍｐ）として出力する比較回路１７と、該パルス信号をクロック信号ｃｌｋに同期して取り込んでビットストリーム信号ｃｈａｒｇｅを出力するフリップフロップＦＦ、および、該ビットストリーム信号のアクティブパルスを計数するカウンタＣＯＵＮＴを備え、当該カウンタによる計数結果をデジタル値として出力する出力回路（制御回路１８）と、上記ビットストリーム信号のアクティブパルス期間に電流を出力して上記積分コンデンサを放電させる放電回路１６とをさらに備えていてもよい。 The optical sensor 1 according to Aspect 9 of the present invention includes, in any one of the Aspects 1 to 7, an integration capacitor (capacitor C1) that stores charges according to the magnitude of the photocurrent, and the integration capacitor stores the integration capacitor. An integration circuit (charging circuit 15) that outputs a voltage corresponding to the amount of charge and the output voltage Vsig of the integration circuit and the reference voltage Vref are compared with each other, and the comparison result is expressed as a binary pulse signal (output). A comparator circuit 17 that outputs the signal as a signal comp), a flip-flop FF that takes the pulse signal in synchronization with the clock signal clk and outputs the bit stream signal charge, and a counter COUNT that counts the active pulses of the bit stream signal. And an output circuit (control circuit 18) for outputting a count result by the counter as a digital value. When, may output a current to the active pulse duration of the bit stream signal be further provided with a discharge circuit 16 for discharging the integrating capacitor.
　上記構成によれば、アクティブパルス期間の合計した長さが、光電流の大きさに応じたものとなる。そして、出力回路の出力パルス電流が積分回路で積分される（すなわち平均化される）ことで、光電流の大きさを示すデジタル値が得られる。これにより、光センサは、受光素子の受光量に応じた光電流の大きさをデジタル値に変換できる。すなわち、光センサは、所望のデジタル処理が可能な受光量を表すデジタル値を出力することができる。 According to the above configuration, the total length of the active pulse period corresponds to the magnitude of the photocurrent. Then, the output pulse current of the output circuit is integrated (that is, averaged) by the integration circuit, so that a digital value indicating the magnitude of the photocurrent is obtained. Thereby, the photosensor can convert the magnitude of the photocurrent corresponding to the amount of light received by the light receiving element into a digital value. In other words, the optical sensor can output a digital value representing the amount of received light that can be processed in a desired manner.
　また、積分回路は、アンプを利用して積分コンデンサに蓄えられる電荷量に対応する電圧を出力する場合に、アンプの非反転入力端子への入力電圧を０Ｖに設定できる。この場合、受光素子のバイアス電圧が０Ｖになり、受光素子は、バイアス電圧が０Ｖでない場合と比較して暗電流を低減できる。すなわち、光センサは、受光量が低く、受光素子から発生する光電流が小さい場合であっても、受光量を正確に測定することができる。換言するならば、光センサは、正確に低感度での受光量を測定することができる。 Also, the integration circuit can set the input voltage to the non-inverting input terminal of the amplifier to 0 V when outputting a voltage corresponding to the amount of charge stored in the integration capacitor using the amplifier. In this case, the bias voltage of the light receiving element becomes 0V, and the light receiving element can reduce the dark current compared to the case where the bias voltage is not 0V. That is, the optical sensor can accurately measure the received light amount even when the received light amount is low and the photocurrent generated from the light receiving element is small. In other words, the optical sensor can accurately measure the amount of received light with low sensitivity.
　本発明の他の態様に係る光センサ１は、上記態様１から９のいずれか１態様において、上記基板上の異なる位置に配された２個の発光素子と、上記複数の受光素子から発生した各光電流を待ち受け、上記基板上の上記複数の受光素子が配された領域に入射する光の強度分布の重心を計算する重心計算手段と、第１の上記発光素子が発光している間に上記重心計算手段により計算された重心と第２の上記発光素子が発光している間に上記重心計算手段により計算された重心との間の距離と所定の閾値とを比較する比較手段と、上記比較手段の比較結果において、上記距離が上記閾値を越えている場合に、光センサにより測定された受光量が正しい値ではない可能性があることを示す信号を出力する信号出力手段とを備えていてもよい。 The optical sensor 1 according to another aspect of the present invention is the light sensor 1 according to any one of the aspects 1 to 9 generated from the two light emitting elements arranged at different positions on the substrate and the plurality of light receiving elements. While waiting for each photocurrent, the center of gravity calculating means for calculating the center of gravity of the intensity distribution of the light incident on the region where the plurality of light receiving elements are arranged on the substrate, and while the first light emitting element emits light A comparing means for comparing a distance between the center of gravity calculated by the center of gravity calculating means and the center of gravity calculated by the center of gravity calculating means while the second light emitting element emits light with a predetermined threshold; A signal output means for outputting a signal indicating that the amount of received light measured by the optical sensor may not be a correct value when the distance exceeds the threshold value in the comparison result of the comparison means; May be.
　上記構成によれば、２個の発光素子から出射された光は、筐体反射光となり受光領域に入射することがある。この場合、２個の発光素子が異なる位置に配されているので、各筐体反射光は、受光領域の異なる領域へ入射する。そして、重心計算手段は、各筐体反射光の入射中心を計算し、比較手段は、各入射中心の間の距離（入射中心間距離）を所定の閾値と比較する。 According to the above configuration, the light emitted from the two light emitting elements may be reflected by the housing and enter the light receiving region. In this case, since the two light emitting elements are arranged at different positions, each case reflected light is incident on different areas of the light receiving area. The center-of-gravity calculating unit calculates the incident center of each case reflected light, and the comparing unit compares the distance between the incident centers (distance between incident centers) with a predetermined threshold.
　ここで、筐体反射光がない場合、入射中心間距離は所定の閾値以下になる。そして、筐体反射光がある場合、入射中心間距離が所定の閾値を越え、信号出力手段が信号を出力するので、光センサは、筐体反射光が受光領域へ入射したか否かを外部へ通知できる。 Here, when there is no casing reflected light, the distance between the incident centers is below a predetermined threshold. When there is case reflected light, the distance between the incident centers exceeds a predetermined threshold value, and the signal output means outputs a signal. Therefore, the optical sensor determines whether the case reflected light is incident on the light receiving area. Can be notified.
　すなわち、光センサは、測定した受光量が正しい値であるか否かを外部へ通知することができる。また、光センサは、少なくとも２個の発光素子を備えることにより、１個の発光素子が壊れた場合であっても、他の発光素子を利用して受光量の測定を続行することができる。 That is, the optical sensor can notify the outside whether or not the measured amount of received light is a correct value. In addition, since the optical sensor includes at least two light emitting elements, measurement of the amount of received light can be continued using another light emitting element even if one light emitting element is broken.
　なお、光センサが備える発光素子の個数は２個に限定されるわけではなく、３個以上であってもよい。 Note that the number of light-emitting elements included in the optical sensor is not limited to two, and may be three or more.
　本発明の態様１０に係る表示装置は、画面を表示する液晶パネル５５と、上記液晶パネルに光を照射するバックライト５２と、上記バックライトの輝度を制御するバックライト制御部５１と、上記態様１から９のいずれか１態様における光センサ１とを備え、上記バックライト制御部は、上記光センサから出力される信号に基づいて、上記バックライトの輝度を制御してもよい。 A display device according to aspect 10 of the present invention includes a liquid crystal panel 55 that displays a screen, a backlight 52 that irradiates light to the liquid crystal panel, a backlight control unit 51 that controls the luminance of the backlight, and the aspect described above. 1 to 9, and the backlight control unit may control the luminance of the backlight based on a signal output from the optical sensor.
　上記構成によれば、表示装置は、周囲の物体の近接を正確に検知できる光センサを備えているので、周囲の物体の近接に応じて、バックライトの輝度制御ができる。また、表示装置は、周囲の光の色成分（照度情報）を正確に検出できる光センサを備えているので、周囲の光の照度に応じて、画面の明るさを正確に制御することができる。 According to the above configuration, since the display device includes the optical sensor that can accurately detect the proximity of the surrounding object, the luminance of the backlight can be controlled according to the proximity of the surrounding object. In addition, since the display device includes an optical sensor that can accurately detect the color component (illuminance information) of the ambient light, the brightness of the screen can be accurately controlled according to the illuminance of the ambient light. .
　なお、光センサから出力される信号が上述のようにアナログ‐デジタル変換されたデジタル値である場合には、バックライト制御部は、デジタル値に基づいてバックライトの輝度を制御してもよい。 If the signal output from the optical sensor is a digital value that has been analog-to-digital converted as described above, the backlight control unit may control the luminance of the backlight based on the digital value.
　本発明の各態様に係る光センサは、コンピュータによって実現してもよく、この場合には、コンピュータを上記光センサが備える各手段として動作させることにより上記光センサをコンピュータにて実現させる光センサの制御プログラム、およびそれを記録したコンピュータ読み取り可能な記録媒体も、本発明の範疇に入る。 The optical sensor according to each aspect of the present invention may be realized by a computer. In this case, the optical sensor is realized by the computer by operating the computer as each unit included in the optical sensor. A control program and a computer-readable recording medium on which the control program is recorded also fall within the scope of the present invention.
　〔付記事項〕
　本発明は上述した各実施形態に限定されるものではなく、請求項に示した範囲で種々の変更が可能であり、異なる実施形態にそれぞれ開示された技術的手段を適宜組み合わせて得られる実施形態についても本発明の技術的範囲に含まれる。さらに、各実施形態にそれぞれ開示された技術的手段を組み合わせることにより、新しい技術的特徴を形成することができる。 [Additional Notes]
The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention. Furthermore, a new technical feature can be formed by combining the technical means disclosed in each embodiment.
　本発明は、携帯電話やデジタルカメラなどに備えられたバックライトの輝度の制御にも利用することができる。 The present invention can also be used to control the brightness of a backlight provided in a mobile phone or a digital camera.
１　光センサ
５　表示装置
１０　制御部
１０ａ　制御部
１０ｂ　制御部
１１　受光素子選択部（受光素子選択手段）
１２　分光特性設定部（分光特性設定手段）
１３　受光量計算部（受光量計算手段）
１５　充電回路（積分回路）
１６　放電回路
１７　比較回路
１８　制御回路（出力回路）
２１　基板
２２　樹脂封止部
２３　レンズ（レンズ形状）
５１　バックライト制御部
５２　バックライト
５５　液晶パネル
ＡＤＣ　アナログ‐デジタル変換部（デジタル変換手段）
Ｃ１　コンデンサ（積分コンデンサ）
ＣＯＵＮＴ　カウンタ
Ｄ　領域
Ｄａ　領域
Ｄｂ　領域
ＦＦ　フリップフロップ
Ｉａ　光電流
Ｉｂ　光電流
Ｉｃ　光電流
Ｉｉｎ　入力電流（光電流）
ＬＥＤ　発光素子
ＰＤ　受光素子
ＰＤＧ　受光素子群
ＰＤｉｒ　赤外光受光用ＰＮ接合（ＰＮ接合）
ＰＤｖｉｓ　可視光受光用ＰＮ接合（ＰＮ接合）
Ｖｒｅｆ　基準電圧
Ｖｓｉｇ　出力電圧
ｃｈａｒｇｅ　ビットストリーム信号
ｃｌｋ　クロック信号
ｃｏｍｐ　出力信号 DESCRIPTION OF SYMBOLS 1 Optical sensor 5 Display apparatus 10 Control part 10a Control part 10b Control part 11 Light receiving element selection part (light receiving element selection means)
12 Spectral characteristic setting section (Spectral characteristic setting means)
13 Light reception amount calculation unit (light reception amount calculation means)
15 Charging circuit (integration circuit)
16 Discharge circuit 17 Comparison circuit 18 Control circuit (output circuit)
21 Substrate 22 Resin sealing part 23 Lens (lens shape)
51 Backlight Control Unit 52 Backlight 55 Liquid Crystal Panel ADC Analog-Digital Conversion Unit (Digital Conversion Unit)
C1 capacitor (integration capacitor)
COUNT Counter D Region Da Region Db Region FF Flip-flop Ia Photocurrent Ib Photocurrent Ic Photocurrent Iin Input current (photocurrent)
LED Light emitting element PD Light receiving element PDG Light receiving element group PDir Infrared light receiving PN junction (PN junction)
PDvis Visible light receiving PN junction (PN junction)
Vref reference voltage Vsig output voltage charge bit stream signal clk clock signal comp output signal

Claims (5)

  1. 　基板を有した、受光量を測定する光センサであって、
    　上記基板上に配された、受光して光電流を発生させる複数の受光素子と、
    　上記複数の受光素子のうち、一部の受光素子を選択する受光素子選択手段と、
    　上記複数の受光素子の分光特性をそれぞれ設定する分光特性設定手段と、
    　上記受光素子選択手段により選択され、かつ、上記分光特性設定手段により分光特性が設定された受光素子から発生した光電流を待ち受け、上記受光量を計算する受光量計算手段とを備えていることを特徴とする光センサ。     An optical sensor having a substrate for measuring the amount of received light,
    A plurality of light receiving elements arranged on the substrate for receiving a photocurrent and generating a photocurrent;
    A light receiving element selecting means for selecting some of the plurality of light receiving elements;
    Spectral characteristic setting means for setting spectral characteristics of the plurality of light receiving elements, respectively;
    A received light amount calculating means for waiting for a photocurrent generated from the light receiving element selected by the light receiving element selecting means and having the spectral characteristics set by the spectral characteristic setting means, and calculating the received light amount. Features an optical sensor.
  2. 　少なくとも赤外光を出射する発光素子をさらに備え、
    　上記受光素子選択手段は、上記複数の受光素子のうち、上記基板上の上記複数の受光素子が配された領域の上記発光素子側に配された一部の受光素子を選択し、
    　上記分光特性設定手段は、上記受光素子選択手段により選択された受光素子の分光特性として、赤外の分光特性を設定することを特徴とする請求項１に記載の光センサ。     A light emitting element that emits at least infrared light;
    The light receiving element selecting means selects a part of the plurality of light receiving elements arranged on the light emitting element side of the region on the substrate where the plurality of light receiving elements are arranged,
    2. The optical sensor according to claim 1, wherein the spectral characteristic setting means sets infrared spectral characteristics as spectral characteristics of the light receiving element selected by the light receiving element selecting means.
  3. 　上記受光素子選択手段は、上記複数の受光素子のうち、上記基板上の上記複数の受光素子が配された領域の中心付近に配された一部の受光素子を選択し、
    　上記分光特性設定手段は、該受光素子選択手段により選択された受光素子の分光特性として、可視～赤外の分光特性と、赤外の分光特性とのいずれかを選択し、
    　上記受光量計算手段は、上記分光特性設定手段により可視～赤外の分光特性が設定されている間に該受光素子から発生する光電流の大きさから、上記分光特性設定手段により赤外の分光特性が設定されている間に該受光素子から発生する光電流の大きさを減算して、上記受光量を計算することを特徴とする請求項１または２に記載の光センサ。     The light receiving element selection means selects a part of the plurality of light receiving elements disposed near the center of the region on the substrate where the plurality of light receiving elements are disposed,
    The spectral characteristic setting means selects one of visible to infrared spectral characteristics and infrared spectral characteristics as the spectral characteristics of the light receiving element selected by the light receiving element selecting means,
    The received light amount calculating means determines the infrared spectral intensity by the spectral characteristic setting means from the magnitude of the photocurrent generated from the light receiving element while the visible to infrared spectral characteristics are set by the spectral characteristic setting means. 3. The optical sensor according to claim 1, wherein the received light amount is calculated by subtracting the magnitude of the photocurrent generated from the light receiving element while the characteristic is set.
  4. 　上記複数の受光素子を封止する樹脂封止部をさらに備え、
    　上記樹脂封止部は、上記基板上の上記複数の受光素子が配された領域に光を集光するレンズ形状を有していることを特徴とする請求項１から３のいずれか１項に記載の光センサ。     It further comprises a resin sealing portion that seals the plurality of light receiving elements,
    The said resin sealing part has a lens shape which condenses light to the area | region where the said several light receiving element on the said board | substrate was distribute | arranged, The any one of Claim 1 to 3 characterized by the above-mentioned. The optical sensor described.
  5. 　画面を表示する液晶パネルと、
    　上記液晶パネルに光を照射するバックライトと、
    　上記バックライトの輝度を制御するバックライト制御部と、
    　請求項１から４のいずれか１項に記載の光センサとを備え、
    　上記バックライト制御部は、上記光センサから出力される信号に基づいて、上記バックライトの輝度を制御することを特徴とする表示装置。
          A liquid crystal panel that displays a screen;
    A backlight for illuminating the liquid crystal panel;
    A backlight control unit for controlling the luminance of the backlight;
    An optical sensor according to any one of claims 1 to 4,
    The display device, wherein the backlight control unit controls the luminance of the backlight based on a signal output from the optical sensor.
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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016167259A1 (en) * 2015-04-15 2016-10-20 シャープ株式会社 Sensor circuit
JP2017005428A (en) * 2015-06-08 2017-01-05 ローム株式会社 proximity sensor
WO2017094278A1 (en) * 2015-11-30 2017-06-08 シャープ株式会社 Photo sensor
CN113407068A (en) * 2020-03-16 2021-09-17 罗姆股份有限公司 Light-receiving IC, non-contact sensor, and electronic device
WO2023042304A1 (en) * 2021-09-15 2023-03-23 日本電気株式会社 Reception control device, reception control method, and recording medium

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0792021A (en) * 1993-09-21 1995-04-07 Kurabo Ind Ltd Optical sensor
JP2003258736A (en) * 2002-03-05 2003-09-12 Microsignal Kk Sensor for spatial optical communication, receiver for spatial optical communication and spatial optical communication system provided with such receiver
WO2008114314A1 (en) * 2007-03-16 2008-09-25 Fujitsu Microelectronics Limited Light receiving device and light receiving method
JP2013050422A (en) * 2011-08-31 2013-03-14 Sharp Corp Sensor circuit and electronic apparatus
WO2014041884A1 (en) * 2012-09-11 2014-03-20 シャープ株式会社 Sensor, display device, mobile telephone, and digital camera

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0792021A (en) * 1993-09-21 1995-04-07 Kurabo Ind Ltd Optical sensor
JP2003258736A (en) * 2002-03-05 2003-09-12 Microsignal Kk Sensor for spatial optical communication, receiver for spatial optical communication and spatial optical communication system provided with such receiver
WO2008114314A1 (en) * 2007-03-16 2008-09-25 Fujitsu Microelectronics Limited Light receiving device and light receiving method
JP2013050422A (en) * 2011-08-31 2013-03-14 Sharp Corp Sensor circuit and electronic apparatus
WO2014041884A1 (en) * 2012-09-11 2014-03-20 シャープ株式会社 Sensor, display device, mobile telephone, and digital camera

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016167259A1 (en) * 2015-04-15 2016-10-20 シャープ株式会社 Sensor circuit
JPWO2016167259A1 (en) * 2015-04-15 2017-11-24 シャープ株式会社 Sensor circuit
CN107615016A (en) * 2015-04-15 2018-01-19 夏普株式会社 Sensor circuit
US10359310B2 (en) 2015-04-15 2019-07-23 Sharp Kabushiki Kaisha Sensor circuit
CN107615016B (en) * 2015-04-15 2019-09-03 夏普株式会社 Sensor circuit
JP2017005428A (en) * 2015-06-08 2017-01-05 ローム株式会社 proximity sensor
WO2017094278A1 (en) * 2015-11-30 2017-06-08 シャープ株式会社 Photo sensor
CN113407068A (en) * 2020-03-16 2021-09-17 罗姆股份有限公司 Light-receiving IC, non-contact sensor, and electronic device
CN113407068B (en) * 2020-03-16 2023-12-05 罗姆股份有限公司 Light receiving IC, noncontact sensor, and electronic device
WO2023042304A1 (en) * 2021-09-15 2023-03-23 日本電気株式会社 Reception control device, reception control method, and recording medium

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