JP2014143100A - Light-emitting device and controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a user not to feel the change of brightness, even if the brightness is changed in order to prolong the life of a light-emitting device.SOLUTION: A control section 120 controls a light-emitting section 100. More specifically, the control section 120 acquires the operation environmental information indicating the operation environment of the light-emitting section 100, and the brightness information indicating the brightness with which the light-emitting section 100 must emit light. The operation environmental information is the operation environmental temperature of the light-emitting section 100, e.g., the temperature of the light-emitting section 100 or the ambient temperature thereof. On the basis of the operation environment and brightness information, the light-emitting section 100 calculates the coefficients to be multiplied by the brightness indicated by the brightness information, and controls the light-emitting section 100 on the basis of the brightness obtained by multiplying the coefficients thus calculated.

Description

  The present invention relates to a light emitting device and a control device.

  One of the light emitting devices uses an organic EL (Organic Electroluminescence) or LED (Light Emitting Diode) as a light source. Such a light-emitting device has a shorter life when the temperature during operation increases.

  In order to deal with such a problem, for example, Patent Documents 1 and 2 describe that the light emission luminance is lowered when the operating environment temperature of the light emitting device exceeds a predetermined value.

  Patent Document 3 describes that when the external temperature of the lighting device increases, the lifetime of the lighting device is extended by reducing the current value or the voltage value supplied to the lighting device.

Japanese Patent Laying-Open No. 2005-31430 JP-A-11-298044 JP 2002-117986 A

  When the brightness desired by the user is high, the user does not feel much change in brightness even if the brightness is reduced. However, when the brightness desired by the user is small, the user may feel a change in brightness if the brightness is further reduced.

  An example of a problem to be solved by the present invention is to prevent a user from perceiving a change in luminance even when the luminance is changed in order to extend the lifetime of the light emitting device.

The invention according to claim 1 is a light emitting unit;
A control unit for controlling the light emitting unit;
With
The controller is
The operating environment information indicating the operating environment of the light emitting unit, and the luminance information indicating the luminance to be emitted by the light emitting unit, and the coefficient to be multiplied by the luminance indicated by the luminance information based on the operating environment and the luminance information To calculate
The light emitting device controls the luminance of the light emitting unit based on a value obtained by multiplying the luminance indicated by the luminance information by the coefficient.

The invention according to claim 6 acquires operating environment information indicating an operating environment of the light emitting unit and luminance information indicating luminance to be emitted by the light emitting unit, and the luminance based on the operating environment and the luminance information. Calculate the coefficient to be multiplied by the brightness indicated by the information,
The control device controls the luminance of the light emitting unit based on a value obtained by multiplying the luminance indicated by the luminance information by the coefficient.

It is a figure which shows the function structure of the light-emitting device which concerns on embodiment. 3 is a diagram illustrating a functional configuration of a light emitting device according to Example 1. FIG. It is a figure which shows the function structure of a control part. It is a figure which shows the relationship between the coefficient (attenuation rate) in Example 1, and the operating environment temperature of a light emission part. It is a figure which shows how the brightness | luminance changes with temperature according to the brightness | luminance which the user desired, when the maximum brightness | luminance of a light emission part is set to 100% in Example 1. FIG. It is a figure which shows the relationship between the coefficient in Example 2, and the operating environment temperature of a light emission part. It is a figure which shows how a brightness | luminance changes with temperature according to the brightness | luminance which the user desired when the maximum brightness | luminance of a light emission part was set to 100% in Example 2. FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate.

  In the following description, each component of each device is not a hardware unit configuration but a functional unit block. Each component of each device includes a CPU, memory, a program that realizes the components shown in the figure loaded in the memory, a storage medium such as a hard disk for storing the program, and a network connection interface. It is realized by any combination of software and software. There are various modifications of the implementation method and apparatus.

  FIG. 1 is a diagram illustrating a functional configuration of a light emitting device 10 according to the embodiment. The light emitting device 10 includes a light emitting unit 100 and a control unit 120. The control unit 120 controls the light emitting unit 100. Specifically, the control unit 120 acquires operating environment information indicating the operating environment of the light emitting unit 100 and luminance information indicating the luminance that the light emitting unit 100 should emit. Then, the control unit 120 calculates a coefficient to be multiplied by the luminance indicated by the luminance information based on the operating environment and the luminance information, and controls the light emitting unit 100 based on the luminance after multiplying the calculated coefficient. Details will be described below.

  The light emitting unit 100 includes a light emitting element. This light emitting element is, for example, an organic EL or LED.

  The operating environment information is, for example, the temperature of the light emitting unit 100 or the temperature around the light emitting unit 100, that is, the operating environment temperature of the light emitting unit 100. These are detected by a sensor and output to the control unit 120. This sensor may be built in the light emitting device 10 or may be provided outside the light emitting device 10.

  As described above, the luminance information indicates the luminance that should be emitted by the light emitting unit 100. The luminance information may be input to the control unit 120 via, for example, an input unit (for example, a switch) provided in the light emitting device 10, or input to the control unit 120 via a controller provided outside the light emitting device 10. May be.

  As described above, the control unit 120 calculates a coefficient to be multiplied by the luminance indicated by the luminance information based on the luminance indicated by the luminance information and the operating environment information. This coefficient is a value of 1 or less, for example, but may be multiplied by a value greater than 1. And the control part 120 controls the light emission part 100 based on the brightness | luminance after multiplying the calculated coefficient.

  As described above, according to the embodiment, the control unit 120 calculates the coefficient to be multiplied by the luminance indicated by the luminance information based on the operating environment and the luminance information, and based on the luminance after multiplying the calculated coefficient, the light emitting unit 100 is controlled. For this reason, the lifetime of the light emitting unit 100 can be extended by multiplying the luminance indicated by the luminance information by a coefficient less than 1.

  Moreover, even if a person changes from a high brightness state to a slightly low state, it is difficult for the person to feel the change. Based on this, the control unit 120 decreases the coefficient as the temperature rises. When the coefficient is set, the luminance information is referred to, and the luminance indicated by the luminance information is small (that is, the luminance desired by the user is small). Is set so that the coefficient is larger than when the luminance indicated by the luminance information is large (that is, when the luminance desired by the user is large), and the amount of decrease in luminance is reduced. In this way, it is possible to prevent the user from feeling a change in luminance.

  In particular, when the light-emitting element included in the light-emitting unit 100 is an element such as an organic EL or LED whose deterioration rate changes greatly depending on temperature, the deterioration rate of the light-emitting element increases as the temperature increases. Therefore, when the operating environment information is the operating environment temperature of the light emitting unit 100, the lifetime of the light emitting unit 100 can be sufficiently extended.

Example 1
FIG. 2 is a diagram illustrating a functional configuration of the light emitting device 10 according to the first embodiment. The light emitting device 10 according to the first embodiment includes a light emitting unit 100, a control unit 120, a temperature detection unit 140, and a luminance information acquisition unit 160. The outline of the light emitting unit 100 and the control unit 120 is the same as that of the embodiment.

  The temperature detection unit 140 is installed in the vicinity of the light emitting unit 100 or as a part of the light emitting unit 100, and detects the temperature of the light emitting unit 100 or the temperature around the light emitting unit 100. The detection value of the temperature detection unit 140 is output to the control unit 120.

  The luminance information acquisition unit 160 acquires luminance information. The luminance information acquisition unit 160 may be a switch operated by a user, for example, or may be a reception unit that receives information transmitted wirelessly from a remote controller.

  FIG. 3 is a diagram illustrating a functional configuration of the control unit 120 in the present embodiment. In the present embodiment, the control unit 120 includes a luminance setting unit 121, a coefficient setting unit 122, a luminance correction unit 123, a driver control unit 124, a driver 125, and a coefficient information storage unit 126.

  The driver 125 is a driver of the light emitting unit 100 and supplies current to the light emitting unit 100. The driver control unit 124 controls the amount of current supplied to the light emitting unit 100 by controlling the driver 125.

  The luminance setting unit 121 processes the luminance information received by the luminance information acquisition unit 160 to recognize the luminance desired by the user. The brightness setting unit 121 transmits the recognized brightness to the coefficient setting unit 122 and the brightness correction unit 123.

  The coefficient setting unit 122 recognizes the operating environment temperature of the light emitting unit 100 based on the signal transmitted from the temperature detection unit 140. Then, the coefficient setting unit 122 sets a coefficient to be multiplied by the luminance recognized by the luminance setting unit 121 based on the recognized operating environment temperature and the luminance transmitted from the luminance setting unit 121. The coefficient information storage unit 126 stores information used when setting the coefficients. Details of this information will be described later.

  The luminance correction unit 123 corrects the luminance by multiplying the luminance recognized by the luminance setting unit 121 by the coefficient set by the coefficient setting unit 122. Then, the luminance correction unit 123 outputs the corrected luminance to the driver control unit 124. The driver control unit 124 controls the driver 125 based on the luminance received from the luminance correction unit 123.

  4 and 5 are diagrams for explaining an example of data stored in the coefficient information storage unit 126. FIG. FIG. 4 is a diagram showing the relationship between the coefficient (attenuation rate) and the operating environment temperature of the light emitting unit 100. FIG. 5 is a diagram showing how the luminance changes depending on the temperature for each luminance (dimming rate) desired by the user when the maximum luminance of the light emitting unit 100 is 100%.

  When following the data shown in FIG. 4, the coefficient setting unit 122 sets the coefficient to 1 when the temperature is equal to or lower than the threshold, and sets the coefficient to a value less than 1 when the temperature exceeds the threshold. In this case, when the temperature is lower than the threshold value, that is, when the deterioration rate of the light emitting unit 100 is slow, the light emitting device 10 emits light with the brightness desired by the user.

  Further, the coefficient setting unit 122 decreases the coefficient as the temperature increases when the temperature exceeds the threshold. In this way, when the continuous light emission time of the light emitting unit 100 becomes longer and the temperature of the light emitting unit 100 gradually increases, the control unit 120 can gradually decrease the luminance of the light emitting unit 100. . In this case, it becomes difficult for the user to recognize that the luminance has changed. In the example shown in this figure, the relationship between the coefficient and the temperature when the operating environment temperature of the light emitting device 10 exceeds the threshold value is a linear function, that is, a linear shape.

  Further, the light emitting unit 100 has a deterioration rate that increases as the luminance increases. On the other hand, in the example illustrated in FIG. 4, the coefficient setting unit 122 sets a threshold value based on the luminance recognized by the luminance setting unit 121 (described as a dimming rate in the drawing). Specifically, the coefficient setting unit 122 decreases the threshold as the luminance recognized by the luminance setting unit 121 increases. That is, the higher the luminance of the light emitting unit 100, the lower the temperature at which the luminance starts to decrease. For this reason, when the luminance of the light emitting unit 100 is high, the deterioration rate of the light emitting unit 100 can be slowed down.

The above-described control can be described by equations as follows, for example. The ratio of the luminance recognized by the luminance setting unit 121 to the maximum luminance of the light emitting unit 100 is D (%), the operating environment temperature of the light emitting unit 100 is T, and the coefficient is A _tt (%). Further, the threshold value in D = 100% as _{T a,} the threshold in D = minimum value and _{T b.} T _c is a temperature at which the coefficient becomes zero.

When T ≦ (T _b − (D / 100) × (T _b −T _a ), _Att = 100%, and T _c ≧ T> (T _b − (D / 100) × (T _b In the case of -T _a ), A _tt satisfies the following formula (1), and in the case of T> T _c , A _tt = 0%.
A _tt = 100 × (T _c −T) / (T _c − (T _b − (D / 100) × (T _b −T _a )))
... (1)

  As described above, according to the present embodiment, the lifetime of the light emitting unit 100 can be further extended, and the user can be prevented from feeling a change in luminance.

(Example 2)
The light emitting device 10 according to the second embodiment has the same configuration as that of the light emitting device 10 according to the first embodiment, except for data stored in the coefficient information storage unit 126.

  FIG. 6 is a diagram showing the relationship between the coefficient (attenuation rate) and the operating environment temperature of the light emitting unit 100 in this embodiment. FIG. 7 is a diagram illustrating how the luminance changes depending on the temperature for each luminance (dimming rate) desired by the user when the maximum luminance of the light emitting unit 100 is 100%.

  In the example shown in the figure, the threshold set for the operating environment temperature of the light emitting unit 100 is constant regardless of the luminance recognized by the luminance setting unit 121. The coefficient setting unit 122 changes the coefficient in a curvilinear manner, for example, in an exponential function.

For example, the coefficient setting unit 122 changes the coefficient _Att so as to satisfy the following. Here, the threshold is _Td . T _c is a temperature at which the coefficient becomes zero.

When T ≦ _Td , A _tt = 100%. Further, when T _c ≧ T> T _d , A _tt satisfies the following expression (2). Further, when T> _Tc , A _tt = 0%.
A _tt = 100 × (1- (T−T _a ) / (T _c −T _a ) ^{(4-D / 100)} ) (2)

  Also according to this embodiment, the same effect as that of Example 1 can be obtained. Further, even if the threshold value is made constant regardless of the luminance recognized by the luminance setting unit 121, the coefficient multiplied by this luminance can be reduced as the luminance recognized by the luminance setting unit 121 increases.

  As mentioned above, although embodiment and the Example were described with reference to drawings, these are illustrations of this invention and can also employ | adopt various structures other than the above.

DESCRIPTION OF SYMBOLS 10 Light-emitting device 100 Light-emitting part 120 Control part 121 Brightness setting part 122 Coefficient setting part 123 Brightness correction part 124 Driver control part 125 Driver 126 Coefficient information storage part 140 Temperature detection part 160 Luminance information acquisition part

Claims (6)

A light emitting unit;
A control unit for controlling the light emitting unit;
With
The controller is
The operating environment information indicating the operating environment of the light emitting unit, and the luminance information indicating the luminance to be emitted by the light emitting unit, and the coefficient to be multiplied by the luminance indicated by the luminance information based on the operating environment and the luminance information To calculate
A light-emitting device that controls the luminance of the light-emitting unit based on a value obtained by multiplying the luminance indicated by the luminance information by the coefficient. The light-emitting device according to claim 1.
The light emitting device, wherein the operating environment information is a temperature of the light emitting unit or a temperature around the light emitting unit. The light-emitting device according to claim 2.
The controller is
If the temperature is below the threshold, set the coefficient to 1,
A light-emitting device that sets the coefficient to a value less than 1 when the temperature exceeds a threshold value. The light emitting device according to claim 3.
The control unit is a light-emitting device that sets the threshold based on the luminance indicated by the luminance information. The light-emitting device according to claim 3 or 4,
The control unit is a light-emitting device that reduces the coefficient as the temperature increases when the temperature exceeds a threshold value. The operating environment information indicating the operating environment of the light emitting unit and the luminance information indicating the luminance to be emitted by the light emitting unit are acquired, and the coefficient to be multiplied by the luminance indicated by the luminance information is obtained based on the operating environment and the luminance information Calculate
A control device that controls the luminance of the light emitting unit based on a value obtained by multiplying the luminance indicated by the luminance information by the coefficient.

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