JP2007334093A - Projector and control method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projector capable of making a user be aware of the abnormal state of an apparatus and to provide a control method for the projector. <P>SOLUTION: When a temperature detected by a temperature sensor 24 is equal to or higher than a first predetermined temperature T1, a main control section 20 instructs an image control section 26 to maximize transmittance of all the pixels included in the image forming area of a liquid crystal light valve 14R for red color. The image control section 26 creates image data corresponding to the content of the instruction by itself and outputs the image data to a light valve drive section 29. On the basis of the image data created by the image control section 26, the light valve drive section 29 drives the liquid crystal light valve 14R for the red color. Further, the main control section 20 instructs a light source drive section 23 to turn off LED light sources 11G and 11B for green light and blue light respectively, thereby projecting onto a screen SC a warning image formed in red color only. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a projector including a plurality of light sources that respectively emit light having different wavelength ranges and a control method thereof.

  In a projector that modulates light emitted from a light source and projects an image on a screen or the like, the projector includes an abnormality detection unit that detects an abnormality that has occurred in the apparatus, such as a temperature abnormality, and a warning display means that notifies the user of the abnormality. A projector provided is known (for example, Patent Document 1). Such a projector is provided with an indicator composed of an LED (light emitting diode) or the like as a warning display means, or a character or symbol representing a warning is synthesized on the peripheral portion of the projected image to warn the user. To do. If the abnormal state continues after the warning, safety measures such as forcibly turning off the light source are taken.

JP-A-5-93953

However, the warning display due to the lighting or blinking of the indicator may not be noticed by the user depending on the positional relationship between the projector and the user, and an abnormal state may be left unattended. For example, when a warning about abnormal temperature is left without being noticed and a safety measure is taken, the user suddenly turns off the light source, which is inconvenient.
Further, in the warning display in which characters, symbols, and the like are combined with the peripheral portion of the projected image, there is a possibility that characters and the like are projected outside the screen depending on the projection situation. Although the projector described in Patent Document 1 changes the zoom state at the time of warning display so that characters and symbols are displayed on the screen, the user can zoom in more than displaying characters and the like. Since the user is confused about the change of the state, there is a problem that the warning content is not easily recognized.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a projector capable of effectively recognizing that a device is in an abnormal state and a control method thereof.

  The projector of the present invention projects a plurality of light sources that respectively emit light having different wavelength ranges, a light modulation device that modulates light emitted by the plurality of light sources, and light that is modulated by the light modulation device, A projection optical system for displaying an image on the projection surface; an abnormality detection unit for detecting an abnormality of the projector; and when the abnormality detection unit detects the abnormality, the luminance of some of the plurality of light sources is adjusted. And a light source driving unit for lowering.

  According to this projector, when the abnormality detection unit detects an abnormality, the light source driving unit decreases the luminance of some of the light sources having different wavelength ranges, so that the color tone of the displayed image is changed. It changes, and it becomes possible to make a user recognize effectively that abnormality has arisen. Furthermore, since the luminance of the light source is reduced, it is possible to suppress power consumption and temperature rise. In particular, when the abnormality detected by the abnormality detection unit is a high temperature abnormality, the abnormal state can be alleviated.

  In the projector, it is preferable that the light source driving unit turns off the part of the light sources when the abnormality detecting unit detects the abnormality.

  According to this projector, when the abnormality detection unit detects an abnormality, the light source driving unit turns off some of the light sources having different wavelength ranges, so that the color tone of the image changes significantly and an abnormality occurs. It becomes possible to recognize more effectively that this has occurred. Furthermore, since the light source is turned off, it is possible to further suppress power consumption and temperature rise.

  In the projector, it is preferable that the light modulation device changes a modulation state so that an amount of light transmitted through the light modulation device is increased when the abnormality detection unit detects the abnormality.

  According to this projector, when the abnormality detection unit detects an abnormality, the light modulation device increases the amount of transmitted light, so that heat generation due to light blocking and absorption by the light modulation device is suppressed, and the temperature rise is further increased. It becomes possible to suppress. Further, since the amount of light to be projected increases, it is possible to more effectively recognize that an abnormality has occurred.

  In this projector, the light source is preferably composed of a solid light source element.

  According to this projector, the light source is composed of a solid-state light source element that can be turned on and off instantly, and has a low burden on the light source even if it is turned off (reduced brightness) and then re-lighted (recovers brightness) immediately. Can be restored to a stable lighting state in a short time from a state where the light is turned off (decrease in luminance), and convenience is improved.

  In the projector, the plurality of light sources include a red light source that emits red light, a green light source that emits green light, and a blue light source that emits blue light. It is desirable to reduce the luminance of the light sources excluding at least the red light source among the plurality of light sources.

  In general, when displaying a color image by combining red light, green light, and blue light emitted from a solid light source element, power consumption of the solid light source element for red light is minimized when white balance is adjusted. For this reason, it becomes possible to further suppress power consumption and temperature rise by reducing the luminance of the light sources except the red light source.

  In the projector, it is preferable that the light source driving unit turns off the light sources excluding at least the red light source among the plurality of light sources when the abnormality detection unit detects the abnormality.

  According to this projector, when the abnormality detection unit detects an abnormality, the light source driving unit turns off the light sources other than at least the red light source among the plurality of light sources. It becomes possible to recognize that it is more effective. Furthermore, since the light source is turned off, it is possible to further suppress power consumption and temperature rise.

  A projector control method according to the present invention is a projector control method that includes a plurality of light sources that respectively emit light having different wavelength ranges, and that modulates and projects the light emitted from the plurality of light sources. A first step of detecting an abnormality, and a second step of reducing luminance of some of the plurality of light sources when the abnormality is detected in the first step. Features.

  According to this projector control method, when an abnormality is detected in the first step, the brightness of some of the light sources having different wavelength ranges is reduced in the second step. The color tone of the displayed image changes, and it is possible to make the user effectively recognize that an abnormality has occurred. Furthermore, since the luminance of the light source is lowered, it is possible to suppress temperature rise and power consumption.

  In the projector control method, in the second step, it is preferable that a part of the plurality of light sources is turned off when the abnormality is detected in the first step.

  According to this projector control method, when an abnormality is detected in the first step, the brightness of some of the light sources having different wavelength ranges is turned off in the second step. It is possible to recognize more effectively that the color tone has changed significantly and an abnormality has occurred. Furthermore, since the light source is turned off, it is possible to further suppress power consumption and temperature rise.

  In addition, when the projector and the control method described above are constructed using a computer provided in the projector, the present invention can read the program for realizing the function or the program can be read by the computer. It is also possible to configure in the form of a recording medium or the like recorded in As recording media, flexible disks, CD-ROMs, magneto-optical disks, IC cards, ROM cartridges, punch cards, printed matter on which codes such as barcodes are printed, projector internal storage devices (memory such as RAM and ROM), Various media that can be read by the computer, such as an external storage device, can be used.

  Hereinafter, a projector according to an embodiment of the present invention will be described with reference to the drawings. The projector according to the present embodiment projects an image according to an image signal input from the outside.

FIG. 1 is a block diagram illustrating a schematic configuration of a projector according to the present embodiment.
As shown in FIG. 1, the projector 1 includes an image projection unit 10 that projects an image. The image projection unit 10 includes an LED light source 11 as a light source, a liquid crystal light valve 14 as a light modulation device, and a projection lens 16 as a projection optical system.

  The LED light source 11 has a plurality of LEDs (Light Emitting Diodes) 11a arranged in a matrix. Solid light source elements such as LED 11a can be reduced in size including a power source compared to discharge light source lamps such as metal halide lamps, and can be instantly turned on and off, and can be turned on again immediately after being turned off. However, it has many advantages as a light source element for a projector, such as being capable of stable light emission with a small burden on the light source, a wide color reproducibility and a long lifetime.

  The liquid crystal light valve 14 has a plurality of pixels formed in a matrix, and the light emitted from the LED light source 11 is modulated for each pixel based on the image signal to form image light corresponding to the image signal. To do. The image light formed by the liquid crystal light valve 14 is enlarged and projected by the projection lens 16 toward a projection surface such as the screen SC.

FIG. 2 is an explanatory diagram for explaining the configuration of the image projection unit 10 in more detail.
As shown in FIG. 2, the LED light source 11 of the present embodiment includes three LED light sources 11R (red light sources) and 11G that emit color lights R, G, and B of three colors (red, green, and blue) having different wavelength ranges. (Green light source) and 11B (blue light source), and the color lights R, G, and B emitted from the LED light sources 11R, 11G, and 11B enter the polarization conversion element 12. The polarization conversion element 12 has a function of aligning with polarized light having a specific polarization direction so that the light from each LED light source 11R, 11G, 11B can be efficiently used by the liquid crystal light valve 14 (14R, 14G, 14B). Have. The polarized light emitted from the polarization conversion element 12 is reflected by the mirror 13 and then illuminates the three liquid crystal light valves 14R, 14G, and 14B, respectively.

  Each of the liquid crystal light valves 14R, 14G, and 14B includes a liquid crystal panel 14a in which liquid crystal is sealed between a pair of transparent substrates, and the inner surface of the liquid crystal panel 14a has a minute area (pixel) with respect to the liquid crystal. Transparent electrodes (pixel electrodes) to which a driving voltage can be applied are formed in a matrix (not shown). In addition, an incident-side polarizing plate 14b and an emission-side polarizing plate 14c are attached to the incident-side surface and the emission-side surface of the liquid crystal panel 14a, respectively. The incident-side polarizing plate 14b and the exit-side polarizing plate 14c can transmit only polarized light having a specific polarization direction, and the incident-side polarizing plate 14b transmits polarized light having the polarization direction aligned by the polarization conversion element 12. It is possible. For this reason, most of each color light irradiated to each liquid crystal light valve 14R, 14G, and 14B permeate | transmits the incident side polarizing plate 14b, and injects into the liquid crystal panel 14a.

  Here, when a driving voltage corresponding to an image signal is applied to each pixel of the liquid crystal panel 14a, the light incident on the liquid crystal panel 14a is modulated according to the driving voltage and has a different polarization direction for each pixel. It becomes polarized light. Of this polarized light, only the polarization component that can be transmitted through the exit-side polarizing plate 14c is emitted from the liquid crystal light valves 14R, 14G, and 14B. That is, the liquid crystal light valves 14R, 14G, and 14B transmit incident light with different transmittances for each pixel according to the image signal, so that image light having gradation is formed for each color light. Image light composed of light of each color emitted from the liquid crystal light valves 14R, 14G, and 14B is incident on the cross dichroic prism 15.

  The cross dichroic prism 15 combines image light of each color emitted from each liquid crystal light valve 14R, 14G, 14B for each pixel to form image light representing a color image. The image light combined by the cross dichroic prism 15 is enlarged and projected by the projection lens 16, and an image is displayed on a projection surface such as the screen SC.

  Returning to FIG. 1, the projector 1 includes a main control unit 20 including a CPU and the like. The main control unit 20 includes a main storage unit 21, an operation unit 22, a light source driving unit 23, a temperature sensor 24, A fan driving unit 25 and an image control unit 26 are connected.

  The main control unit 20 functions as a computer and performs overall control of the operation of the projector 1 according to a control program stored in the main storage unit 21. The main storage unit 21 includes a ROM (Read Only Memory) such as a flash memory, a RAM (Random Access Memory), and the like, and stores the control program and is used for storing various setting values. The operation unit 22 includes a plurality of keys for performing various instructions to the projector 1 such as power on / off and image quality adjustment. When the user operates the operation unit 22, The unit 22 outputs an operation signal corresponding to the operation content to the main control unit 20.

  The light source driving unit 23 turns on and off the LED light source 11 by controlling power supply to the LED light source 11 based on an instruction from the main control unit 20. The temperature sensor 24 is configured by a thermistor or the like, and can detect the internal temperature of the projector 1, and outputs a detection signal corresponding to the detected temperature to the main control unit 20. The fan drive unit 25 can drive the air cooling fan 27 based on an instruction from the main control unit 20 to cool the inside of the projector 1. The temperature sensor 24 and the air cooling fan 27 are not limited to one each, and may be provided for each part requiring temperature management, such as the LED light source 11 and the liquid crystal light valve 14.

  Here, the main control unit 20 recognizes the internal temperature of the projector 1 based on the detection signal from the temperature sensor 24 and controls the cooling by the air cooling fan 27, while the internal temperature remains in spite of the cooling by the air cooling fan 27. When the temperature rises to a predetermined temperature or higher (for example, when the air flow is blocked by an obstacle or the like placed near the air inlet or outlet of the air cooling fan 27), it is determined that the device is abnormally hot. . That is, the temperature sensor 24 and the main control unit 20 correspond to the abnormality detection unit of the present invention.

  The image control unit 26 is connected to the receiver 28 and the light valve driving unit 29, and based on instructions from the main control unit 20, various processes for the image signal input to the receiver 28 and the image by the liquid crystal light valve 14. Control the formation.

  An image signal supplied from the outside is input to the receiver 28, converted into image data in a format that can be processed by the image control unit 26, and then output to the image control unit 26. The image control unit 26 converts the resolution of the image data input from the receiver 28 to the resolution (number of pixels) of the liquid crystal light valve 14, various image quality adjustments such as brightness adjustment, contrast adjustment, sharpness adjustment, Alternatively, a process for synthesizing an OSD (on-screen display) image such as a menu or a message is performed and output to the light valve drive unit 29.

  The light valve drive unit 29 generates a drive signal for driving the liquid crystal light valve 14 according to the input image data. The liquid crystal light valve 14 modulates the light source light according to this drive signal, whereby image light corresponding to the image data is formed and projected from the projection lens 16.

Here, an image forming method of the liquid crystal light valve 14 will be described with reference to the drawings.
3A to 3D are explanatory views for explaining an image forming method of the liquid crystal light valve 14 (14R, 14G, 14B), and show a front view of the liquid crystal light valve 14. FIG.

  As shown in FIG. 3A, the liquid crystal panel 14a of each of the liquid crystal light valves 14R, 14G, and 14B includes a pixel region 18a in which a plurality of pixels 18p are arranged in a matrix. Image light (image) corresponding to the image signal is formed by adjusting the transmittance of each pixel 18p according to the drive signal from the light valve drive unit 29. The pixel area 18a of the present embodiment has an aspect ratio (Ax: Ay) of 4: 3, and when displaying an image with an aspect ratio of 4: 3, the entire pixel area 18a forms an image. .

On the other hand, as shown in FIGS. 3B to 3C, when an image is formed using a partial area in the pixel area 18a (hereinafter referred to as an image forming area 18e), the image forming area 18e. An image corresponding to the image signal is formed therein, and the transmittance of all the pixels 18p included in the area outside the image forming area 18e (invalid area 18n) is set to the minimum value.
For example, when displaying an image with an aspect ratio (16: 9, etc.) different from the aspect ratio (4: 3) of the pixel area 18a, as shown in FIG. An image forming area 18e having the same aspect ratio is defined, and an image is formed in the image forming area 18e. In addition, when electronic zoom is performed in which the size of the projected image is changed according to the size of the image formed on the liquid crystal light valve 14, as shown in FIG. 3C, an image forming area having a size corresponding to the zoom magnification. When an image is formed in 18e and the trapezoidal distortion of projection light due to tilt projection is suppressed, as shown in FIG. 3D, a trapezoidal image formation region in which the projection image due to tilt projection becomes rectangular. An image is formed in 18e.

Next, the operation of the projector 1 according to the present embodiment will be described with reference to the drawings.
FIG. 4 is a flowchart for explaining the operation of the projector 1 that is projecting an image. While the projector 1 projects an image according to the image signal, the projector 1 controls the air cooling fan 27 according to the detection signal from the temperature sensor 24, while performing an operation according to the flow shown in FIG.

  As shown in FIG. 4, in step S101, the main control unit 20 determines whether or not the temperature detected by the temperature sensor 24 is equal to or higher than a first predetermined temperature T1 (a temperature that is a guide for determining whether the temperature is normal or abnormal). to decide. If the temperature is lower than the first predetermined temperature T1, it is determined that the internal temperature of the projector 1 is normal, and this step is repeated. If the temperature is equal to or higher than the first predetermined temperature T1, it is determined that the temperature is abnormal and step S102 is performed. Migrate to

  When the process proceeds to step S102, the main control unit 20 starts warning display for the user using the projection image. Specifically, the main control unit 20 instructs the image control unit 26 to maximize the transmittance of all the pixels 18p included in the image forming region 18e of the liquid crystal light valve 14R for red light. To do. The image control unit 26 generates image data corresponding to the instruction content and outputs the image data to the light valve driving unit 29. The light valve driving unit 29 uses the red light for the red light based on the image data generated by the image control unit 26. The liquid crystal light valve 14R is driven (step S102a). Further, the main control unit 20 instructs the light source driving unit 23 to turn off the LED light sources 11G and 11B for green light and blue light (step S102b), thereby generating a warning image in which the entire image is a single red color. Project onto the screen SC. The light valve driving unit 29 continues driving the liquid crystal light valves 14G and 14B for green light and blue light according to the image data input from the receiver 28, but the LED light sources 11G and 11B Since it turns off, it is not reflected in the projected image.

  In step S103, the main control unit 20 waits for a predetermined time (for example, several seconds) while displaying the warning.

  When the predetermined time has elapsed and the process proceeds to step S104, the main control unit 20 instructs the image control unit 26 to drive the liquid crystal light valve 14R for red light according to the image data from the receiver 28. At the same time, the light source driving unit 23 is instructed to relight the LED light sources 11G and 11B for green light and blue light. As a result, the warning display ends, and the projection of the image according to the image signal resumes.

  After recognizing that the projector 1 is abnormally hot due to the warning display, the user turns off the power of the projector 1 or eliminates the cause of the abnormal temperature (for example, the air cooling fan 27). If there are obstacles near the intake and exhaust ports, they must be removed).

  In step S105, the main control unit 20 determines whether or not the detected temperature from the temperature sensor 24 is equal to or higher than the first predetermined temperature T1, and if it is still higher than or equal to the first predetermined temperature T1, step S106. Migrate to On the other hand, for example, when the detected temperature becomes lower than the first predetermined temperature T1 as a result of eliminating the cause of the abnormal high temperature by the user, the process returns to step S101.

  In step S106, the main control unit 20 uses a second predetermined temperature T2 (a temperature serving as a guideline for determining whether or not to perform safety measures) that is detected from the temperature sensor 24 higher than the first predetermined temperature T1. ) Judge whether or not it is above. If the temperature is lower than the second predetermined temperature T2, the process returns to step S105. If the temperature exceeds the second predetermined temperature T2, the process proceeds to step S107.

  When the internal temperature becomes equal to or higher than the second predetermined temperature T2 and the process proceeds to step S107, the main control unit 20 is dangerous for the device that the lighting of the LED light source 11 (11R, 11G, 11B) continues further. Is determined, the light source driving unit 23 is instructed to turn off the three LED light sources 11R, 11G, and 11B, and then the process ends.

As described above, according to the projector 1 of the present embodiment, the following effects can be obtained.
(1) According to the projector 1 of the present embodiment, when the temperature detected by the temperature sensor 24 becomes equal to or higher than the first predetermined temperature T1, the main control unit 20 instructs the light source driving unit 23 to The two LED light sources 11G and 11B are turned off. As a result, the projected image is switched to an image formed only by red light, so that the user can be effectively recognized that an abnormality has occurred. Further, by turning off the LED light sources 11G and 11B, the power consumption of the projector 1 and an increase in the internal temperature are suppressed, and it becomes possible to alleviate the abnormal state of high temperature.

  (2) According to the projector 1 of the present embodiment, when the temperature detected by the temperature sensor 24 becomes equal to or higher than the first predetermined temperature T1, the main control unit 20 instructs the image control unit 26 to turn red. The transmittance in the image forming area 18e of the light liquid crystal light valve 14R is maximized. As a result, the amount of light transmitted through the liquid crystal light valve 14R is increased, and the amount of light absorbed by the exit-side polarizing plate 14c is reduced. Therefore, heat generation due to light being absorbed by the exit-side polarizing plate 14c is suppressed, and the temperature rises. Can be further suppressed. Further, by maximizing the transmittance, the amount of light to be projected increases, so that it is possible to more effectively recognize that an abnormality has occurred.

  (3) According to the projector 1 of the present embodiment, the solid-state light source element (LED 11a) that can be turned on and off instantaneously and has a small burden on the light source even if it is turned on again (luminance recovery) immediately after it is turned off (decrease in luminance). Since the light source is configured as described above, it is possible to return the light source from a light-off state (decrease in luminance) to a stable light-on state in a short time, and convenience is improved.

  (4) According to the projector 1 of the present embodiment, when the temperature detected by the temperature sensor 24 becomes equal to or higher than the first predetermined temperature T1, the two LED light sources 11G and 11B except the red light LED light source 11R are connected. Turned off. In general, when a color image is displayed by combining red light, green light, and blue light emitted from an LED, the power consumption of the red light LED is minimized when white balance is adjusted. For this reason, it becomes possible to further suppress power consumption and temperature rise by turning off the two LED light sources 11G and 11B except the LED light source 11R for red light.

(Modification)
In addition, you may change embodiment of this invention as follows.
In the said embodiment, although the LED light source 11 comprised by LED11a is used, if it has the several light source which each inject | emits the light from which a wavelength range differs, electroluminescence (EL), a semiconductor laser (LD), etc. Other solid light source elements may be used, and a light source other than the solid light source may be used.

  In the above embodiment, when the internal temperature of the projector 1 is equal to or higher than the first predetermined temperature T1, the two LED light sources 11G and 11B are turned off, but the luminance of the LED light sources 11G and 11B is reduced by a predetermined amount. The same effect can be obtained by just using this. In this case, when the warning display is terminated, the lowered luminance of the LED light source may be restored. Note that turning off the LED light source can be considered as one form of reducing the luminance of the LED light source.

  In the embodiment, when the internal temperature of the projector 1 is equal to or higher than the first predetermined temperature T1, the transmittance in the image forming area 18e of the liquid crystal light valve 14R is maximized, but the entire pixel area 18a is transmitted. The rate may be maximized. Further, the transmittance to be set is not limited to the maximum value, and may be any transmittance that can be recognized as a warning, and may be a transmittance higher than the average transmittance in the liquid crystal light valve 14R for red light. For example, the effect (2) of the above embodiment, that is, the effect of suppressing the generation of heat due to the absorption of light in the exit-side polarizing plate 14c can be obtained.

  In the above embodiment, when the internal temperature of the projector 1 is equal to or higher than the first predetermined temperature T1, the transmittance in the image forming area 18e of the liquid crystal light valve 14R is maximized. You may make it continue the image formation according to data. Even in this case, when the LED light sources 11G and 11B are turned off, the image is switched to an image composed of only red light, so that it is possible to effectively recognize that an abnormality has occurred. Further, in this case, the image control unit 26 only needs to perform the same operation processing as before the warning display, so that the control for displaying the warning becomes easy. Alternatively, warning image data may be stored in the main storage unit 21 in advance, and an image (message or the like) based on the warning image data may be projected only with red light.

  In the embodiment, when the internal temperature of the projector 1 becomes equal to or higher than the first predetermined temperature T1, the two LED light sources 11G and 11B are turned off, and a warning display is performed using only the LED light source 11R for red light. However, the warning display mode is not limited to this, and warning display may be performed using another LED light source for color light, or warning is performed using two LED light sources with only one LED light source turned off. Display may be performed.

  In the embodiment, after the warning display, the LED light source 11 is turned off when the internal temperature of the projector 1 further increases. However, after the warning display, the LED light source 11 is turned off after a predetermined time has elapsed. You may do it.

  In the above embodiment, the warning display is performed only once after the internal temperature of the projector 1 becomes equal to or higher than the first predetermined temperature T1, but the warning display may be performed a plurality of times at intervals. .

  In the above embodiment, the warning display when the internal temperature of the projector 1 is equal to or higher than the predetermined temperature (in the case of a high temperature abnormality) has been described. However, the abnormality to be displayed is not limited to the high temperature abnormality, and other abnormal states It is also applicable to the warning display. For example, the warning display according to the present invention may be performed in order to notify that the cover for replacing the light source is open and dangerous.

  In the above embodiment, the color image is formed using the three color (red, green, and blue) color lights R, G, and B emitted from the three LED light sources 11R, 11G, and 11B. ) Is not limited to three. For example, the present invention can be applied to a case where a color image is formed with four colors obtained by adding cyan (C) to the three colors.

  In the above-described embodiment, a plurality of transmission type liquid crystal light valves 14 are used as the light modulation device. However, only one transmission type liquid crystal light valve may be used. It is also possible to use a reflective light modulator such as a reflective liquid crystal light valve. Furthermore, a minute mirror array device that modulates the light emitted from the light source can be used by controlling the emission direction of the incident light for each micromirror as a pixel.

FIG. 2 is a block diagram showing a schematic configuration of a projector. Explanatory drawing for demonstrating in detail the structure of an image projection part. (A)-(d) is explanatory drawing for demonstrating the image formation method of a liquid crystal light valve. 7 is a flowchart for explaining the operation of a projector that is projecting an image.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Projector, 10 ... Image projection part, 11, 11R, 11G, 11B ... LED light source, 11a ... LED, 12 ... Polarization conversion element, 13 ... Mirror, 14, 14R, 14G, 14B ... Liquid crystal light valve, 14a ... Liquid crystal Panel, 14b ... Incident side polarizing plate, 14c ... Emission side polarizing plate, 15 ... Cross dichroic prism, 16 ... Projection lens, 18a ... Pixel region, 18e ... Image forming region, 18p ... Pixel, 20 ... Main control unit, 21 ... Main storage unit 22 ... Operation unit 23 ... Light source drive unit 24 24 Temperature sensor 25 25 Fan drive unit 26 Image control unit 27 Air cooling fan 28 Receiver 29 Light valve drive unit T1 1st predetermined temperature, T2 ... 2nd predetermined temperature.

Claims (8)

A plurality of light sources each emitting light having different wavelength ranges;
A light modulation device that modulates light emitted from the plurality of light sources;
A projection optical system that projects light modulated by the light modulator and displays an image on a projection surface;
An abnormality detection unit for detecting an abnormality of the projector;
A light source driving unit that reduces the luminance of some of the light sources when the abnormality detection unit detects the abnormality; and
A projector comprising:   The projector according to claim 1, wherein the light source driving unit turns off the part of the light sources when the abnormality detecting unit detects the abnormality.   3. The projector according to claim 1, wherein when the abnormality detection unit detects the abnormality, the light modulation device changes a modulation state so that an amount of light transmitted through the light modulation device is increased. A projector characterized by changing.   4. The projector according to claim 1, wherein the light source includes a solid light source element. 5.   The projector according to claim 4, wherein the plurality of light sources include a red light source that emits red light, a green light source that emits green light, and a blue light source that emits blue light, and the light source driving unit includes: When the abnormality detecting unit detects the abnormality, the projector reduces the luminance of light sources excluding at least the red light source among the plurality of light sources.   6. The projector according to claim 5, wherein the light source driving unit turns off light sources other than at least the red light source among the plurality of light sources when the abnormality detection unit detects the abnormality. Projector. A projector control method comprising a plurality of light sources each emitting light having different wavelength ranges, and modulating and projecting light emitted from the plurality of light sources,
A first step of detecting an abnormality of the projector;
A second step of reducing the luminance of some of the plurality of light sources when the abnormality is detected in the first step;
A projector control method comprising: 8. The projector control method according to claim 7, wherein in the second step, when the abnormality is detected in the first step, some of the plurality of light sources are turned off. A projector control method characterized by the above.

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