JP4254317B2 - Display device, projector, and driving method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a projector, a display device, and a driving method thereof.
[0002]
[Prior art]
In conventional projectors, halogen lamps have long been used as light sources, and in recent years, high-intensity, high-efficiency, and long-life high-pressure mercury lamps (UHP) have been used as light sources. However, these lamps require a high-voltage power circuit, and this large and heavy power circuit hinders the reduction in size and weight of the projector.
Therefore, recently, LEDs have attracted attention as a new light source. LEDs are ultra-compact, ultra-light, and have a long life. It is also promising as a light source for projectors, and application development for small and portable small screen projectors has already begun (see Patent Document 1). At present, the efficiency of LEDs is still about 1/2 to 1/3 that of UHP, but it is steadily improving year by year due to remarkable technological innovation.
[0003]
In addition, in the light source using UHP which is a discharge type lamp, in addition to the problems such as the large size and short life as described above, there is a problem that it is almost impossible to control the light source (fast turning on / off, modulation). is there. In other words, the discharge lamp is limited to use with constant output and continuous lighting, and takes a long time of about several minutes to start up. On the other hand, the LED has an advantage that it can freely turn on / off and adjust the amount of emitted light by controlling the drive current.
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 2000-112031
[0005]
[Problems to be solved by the invention]
By the way, in the case of a low-cost projector that places importance on portability, a so-called single-plate projector configuration having only one light modulation means such as a liquid crystal light valve is advantageous. In a single-plate projector using a white light source such as UHP, RGB primary color light is selected in a time-sharing manner (time-sequentially) using a normally rotating color filter, and each pixel of the spatial light modulator is synchronized with it. An image is created by turning on and off. On the other hand, since a projector using an LED light source can sequentially turn on RGB LEDs at high speed, a general idea is to create a primary color light in which RGB is switched in a similar time sequential manner. It is.
[0006]
Although the LED light source is suitable for small and portable small screen projectors as described above, the efficiency of the LED is not far from UHP and is expected to increase in the future. Therefore, it must be said that the development of a product with high brightness is extremely difficult. Further, in the single-plate projector having the above-described configuration, the LEDs of each color are lit in time sequence, and instantaneously always output only one of RGB colors, so it is difficult to increase the brightness. At the present time, the efficiency of LEDs differs greatly depending on the color of light emitted, and in order to achieve color balance, other LEDs must be matched with dark LEDs. This is another obstacle to increasing the brightness of LED light source projectors. It has become.
[0007]
The present invention has been made to solve the above-described problems, and is a display device that displays time-divided color light emitted from a plurality of light sources having different emission colors, and that requires high-luminance display. It is an object of the present invention to provide a projector, a display device, and a driving method thereof that can easily cope with the environment.
[0008]
[Means for Solving the Problems]
In a small and portable small screen projector, every place is assumed as a use environment. For example, it is not difficult to imagine that a projection display device for a camera-equipped mobile phone can be used by a plurality of people to enjoy images indoors, in public places, outdoors, and the like. In such a case, the user may appreciate the beautiful color carefully, or the display brightness may be required for anything such as outdoors.
The present invention has been made based on the above considerations, and provides a display device that allows a user to comfortably view an image in accordance with the usage environment.
[0009]
In order to solve the above problems, a display device of the present invention includes a plurality of light sources having different emission colors and a light modulation unit that modulates color light emitted from the light sources, and the plurality of light sources emit light sequentially. And a display device for driving the light modulation means in time sequence in synchronization with the color light emitted from the light source, the display light control unit for emitting the light sources in time sequence, and the display light control unit. And an offset light control unit that continuously emits each light source with a predetermined output.
According to this configuration, the offset light control unit that operates independently of the display light control unit can cause each light source to emit light continuously at a time other than its own light emission timing. The amount of light can be substantially improved, and a high display luminance can be obtained as necessary. Therefore, according to the present invention, it is possible to provide a display device that can change the display brightness in accordance with the use environment and allows the user to comfortably view the video.
[0010]
In the display device of the present invention, light source control by the display light control unit and light source control by the offset light control unit may be switchable. According to this configuration, it is possible to switch between a mode in which display is performed by sequentially emitting light from a light source and a mode in which display is performed by continuously emitting light from a light source. Display can be performed in the display mode, and in scenes where display brightness is more important than color (such as outdoors in the daytime), display can be performed in a high-brightness display mode in which the light source continuously emits light.
[0011]
In the display device of the present invention, it is preferable that the offset light control unit can adjust the display brightness of the display device by causing each light source to emit light at a predetermined output ratio. According to this configuration, since it is possible to freely adjust the display color and the display luminance, it is possible to view the image while adjusting the display luminance more finely, and the display device has excellent usability. Can be provided.
[0012]
The display device of the present invention includes a photometric unit capable of measuring the light emission amount of each light source, and the light source control unit controls the output of each light source based on the photometric result output from the photometric unit. A possible configuration may also be adopted.
According to this configuration, since the output of each light source can be adjusted based on the actual light emission amount, the accuracy during light amount adjustment is improved, and a high-quality display image can be provided.
[0013]
In the display device having the above-described configuration, the light source control unit can adjust the color balance between the color lights by adjusting the output of the light sources based on the photometric result of the light amount detection unit. preferable.
According to this configuration, it is possible not only to adjust the output signal of each light source, but also to monitor the light emission amount actually output from the light source, so that the display color balance can be optimally adjusted. Become.
[0014]
In the display device of the present invention, when the light emission amount of any of the plurality of light sources is equal to or less than a predetermined light amount, a configuration in which the light source is continuously emitted with a predetermined output by the offset light control unit can be applied.
Even if an abnormality such as a decrease in the amount of light occurs in each light source, it is possible to detect it quickly and reliably, so when it is detected that the light amount of any of the multiple light sources has decreased, It is possible to prevent the display information from being lost by emitting light at the light emission timing of the light source whose light amount has decreased. Therefore, according to this configuration, it is possible to provide a display device having excellent operation reliability.
[0015]
In the display device of the present invention, the offset light control unit may be provided corresponding to each of the plurality of light sources. According to this configuration, the offset light in each of the light sources can be controlled independently of each other. Therefore, not only the display luminance can be controlled, but also the color tone can be adjusted according to the user's preference and usage environment, and the display is easy to use. Equipment can be provided.
[0016]
Next, a projector according to the present invention includes the above-described display device according to the present invention and a projection unit that projects light modulated by the light modulation unit.
According to this configuration, it is possible to provide a projector that can change the display brightness in accordance with the use environment and allows the user to comfortably view the video.
[0017]
Next, the display device driving method of the present invention includes a plurality of light sources having different emission colors and a light modulation unit that modulates the color light emitted from the light sources, and the plurality of light sources emit light sequentially in time. A display device driving method for driving the light modulation means in time sequence in synchronization with the color light emitted from the light source, the display light control unit for emitting the plurality of light sources in time sequence, and the plurality of light sources A display device having a light source control unit having an offset light control unit that continuously emits a light source at a predetermined output, and a mode in which the display light control unit causes the display light control unit to emit light sequentially in time, and The offset light control unit displays an image while freely switching between a mode in which the light source continuously emits light with a predetermined output.
According to this driving method, since the display is performed by freely switching between the mode in which the light source is sequentially emitted and the mode in which the light source is continuously emitted to perform the display, when viewing in beautiful colors It can be displayed in the normal display mode, and in scenes where display brightness is more important than color (such as outdoors in the daytime), it is possible to display in a high-brightness display mode in which the light source is continuously emitted. .
[0018]
The display device driving method of the present invention includes a plurality of light sources having different emission colors, and a light modulation unit that modulates the color light emitted from the light sources, and the light sources emit light sequentially in time. A display device driving method for driving the light modulation means in time sequence in synchronization with the color light emitted from the display device, the display light control unit for emitting the plurality of light sources in time sequence, and the plurality of light sources in a predetermined manner The display device includes a light source control unit having an offset light control unit that continuously emits light with an output of the plurality of light sources, and the display light control unit causes the display light control unit to emit light sequentially in time, and the offset light control unit outputs a predetermined output. The display is performed by continuously emitting light.
According to this driving method, it is possible to freely adjust the display color and the display luminance, so that it is possible to view an image while adjusting the display luminance more finely.
[0019]
The display device driving method of the present invention uses a display device provided with a photometric means capable of measuring the light emission amount of the light source, and the light source control means controls each of the light sources based on a photometric result obtained by the photometric means. The color balance between each color light output from is adjusted.
According to this driving method, since the output of each light source can be adjusted based on the actual light emission amount, the accuracy during light amount adjustment is improved, and a high-quality display image can be provided. .
[0020]
According to the display device driving method of the present invention, when the light amount of any of the plurality of light sources is equal to or less than a predetermined light amount in the photometric result of the photometric means, the offset light control unit continuously causes the light source to be output at a predetermined output. The display brightness is compensated by emitting light.
According to this driving method, even if the light emission amount of one of the light sources is reduced, display is performed with the brightness compensated for by the other light sources, so that the color tone changes but the display information is lost. Therefore, the display operation can be performed safely.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[Display device]
FIG. 1 is a schematic configuration diagram showing a projection type display device (projector) which is an embodiment of a display device according to the present invention, and FIG. 2 is a timing chart in the display operation of the projection type display device of this embodiment. It is. The projection type liquid crystal display device shown in FIG. 1 realizes color display by sequentially switching and projecting images corresponding to the respective colors with a single liquid crystal light valve (light modulation means). In the figure, reference numeral 10 denotes an illumination device, 30 denotes a light amount sensor (photometric means), 40 denotes a liquid crystal light valve (light modulation means), and 50 denotes a projection means (projection lens).
[0022]
The illuminating device 10 is mainly configured by a light source 20R that emits red light, a light source 20G that emits green light, and a light source 20B that emits blue light, and emits red light, green light, and blue light, for example, 180 degrees. The output can be switched in time sequence every minute of one second. The light sources 20R, 20G, and 20B can be composed of a light emitting diode (LED), an organic electroluminescence element (organic EL element), an inorganic electroluminescence element (inorganic EL element), or the like.
[0023]
As the light amount sensor 30, for example, one having an active element such as a photodiode or a phototransistor can be applied. In the case of the present embodiment, a signal amplifying means 61 for amplifying an output from the light amount sensor 30 and an amplified output. A signal is connected to a light source driving circuit (light source control means) 60 through an A / D converter 62 that converts an analog signal into a digital signal. The light source driving circuit 60 is connected to the three light sources 20R, 20G, and 20B and is configured to be able to control the outputs (light emission amount, light emission timing, etc.) of these light sources.
[0024]
In FIG. 1, only one set of the light quantity sensor 30, the signal amplifying means 61, and the A / D converter 62 is shown. However, in practice, the light source 20R is shown. , 20G, and 20B, at least one light quantity sensor 30 is provided, and for each light quantity sensor 30, a signal amplification means 61 and an A / D converter 62 are provided. The respective light amounts of the light sources 20R, 20G, and 20B can be measured.
[0025]
As shown in FIG. 1, the light source drive circuit 60 mainly includes a signal pattern storage unit 66, a drive signal generation unit 67, an offset light application unit 68, a calculation means 65, and D / A conversion units 64a to 64c. It is configured as. Each of the D / A converters 64a to 64c has an input side connected to the calculation unit 65 and an output side connected to the corresponding light sources 20R, 20G, and 20B, and is output from the calculation unit 65. The digital signal is converted into an analog signal and output to each light source.
The calculation means 65 is connected to the signal pattern storage unit 66, the offset light application unit 68, and the drive signal generation unit 67, and is connected to the light amount sensor 30.
[0026]
The projection display device switches the display of the liquid crystal light valve 40 in time sequence in synchronization with each color light emitted from the illumination device 10 in time sequence, and the color light modulated by the liquid crystal light valve 40 is transmitted through the projection device 50. Projecting on a screen.
Specifically, as shown in FIG. 2, one frame is time-divided into three, and red light, blue light, and green light are sequentially emitted from the light sources 20R, 20G, and 20B, and from the light sources 20R, 20G, and 20B. The liquid crystal light valve 40 is driven in accordance with the light emission timing of the irradiated light, and image signals corresponding to the respective color lights are output. While the red light (R) is being output, the liquid crystal light valve 40 outputs an image signal SR corresponding to the red light (R). Similarly, for the other color lights, while the green light (G) or the blue light (B) is output from the light sources 20G and 20B, the image signals SG corresponding to the respective color lights by the liquid crystal light valve 40, or An image signal SB is output. A color image can be synthesized and displayed for each frame based on image signals SR, SG, and SB corresponding to red light, green light, and blue light.
[0027]
The light source driving circuit 60 according to the present embodiment performs an output (signal pattern) from the signal pattern storage unit 66 and an output (driving waveform) from the drive signal generation unit 67 in the calculation unit 65 when performing a normal display operation. And a timing signal), a light source driving signal to be output to each light source is generated, and the light source driving signal is output to each of the light sources 20R, 20G, and 20B via the D / A converters 64a to 64c. Thus, the light sources 20R, 20G, and 20B are caused to emit light sequentially in time. Therefore, in the light source drive circuit 60 of the present embodiment, the display light control unit that causes each light source to emit light sequentially in time is configured mainly by the signal pattern storage unit 66, the drive signal generation unit 67, and the calculation means 65. Yes.
[0028]
In the projection display device according to the present embodiment, the light amount sensor 30 measures the light emission amount of each of the light sources 20R, 20G, and 20B during the display operation, and the measurement result is sent to the light source drive circuit 60. The light emission state of each light source is monitored. Thereby, when the light source drive signal is generated by the arithmetic unit 65, based on feedback information (actual light emission amount of each light source) input from the light amount sensor 30 via the signal amplification unit 61 and the A / D conversion unit 62, The output of each light source 20R, 20G, 20B can also be adjusted. Specifically, for example, when there is a difference between the output balance in the light source drive signal output to each of the light sources 20R, 20G, and 20B and the light amount balance detected by the light amount sensor 30, it is stored in advance. The output balance of each light source can be adjusted so that a light quantity balance can be obtained. Alternatively, it is possible to display a color tone in which a specific color is emphasized by reflecting a parameter adjusted according to the user's preference or the like.
[0029]
Further, the light source driving circuit 60 is provided with an offset light application unit 68. Based on the output from the offset light application unit 68, the calculation means 65 sequentially sets the light sources 20R, 20G, and 20B in time order. A light source driving signal is generated by superimposing a signal to be emitted and a signal for causing each light source to continuously emit light at a predetermined output, and is output to the light sources 20R, 20G, and 20B via the D / A converters 64a to 64c. It is like that. In this case, each of the light sources 20R, 20G, and 20B emits light continuously at a predetermined output at a time other than the light emission timing for generating a display image, so that the amount of light applied to the liquid crystal light valve 40 increases and the display luminance is increased. improves.
In the light source drive circuit 60 of the present embodiment, the offset light control unit that causes each light source to continuously emit light at a predetermined output is configured mainly by the offset light application unit 68 and the calculation means 65.
[0030]
In the above description, the light source driving signal is generated by superimposing the signal for causing the light sources 20R, 20G, and 20B to emit light sequentially in time and the signal for causing continuous light emission at a predetermined output by the calculation means 65. Can be operated so as to stop only the signals for sequentially emitting light for the above time and output only the signals for causing each light source to continuously emit light as the light source drive signal. In this operation, light in which each color light output from the light sources 20R, 20G, and 20B is mixed is used as display light, and the projected display is monochrome display.
[0031]
[Driving method]
Next, a method for driving a display device according to the present invention will be described with reference to the drawings.
The projection display device of the above embodiment emits the light sources 20R, 20G, and 20B sequentially in time, and performs light modulation by the liquid crystal light valve 40 based on image information corresponding to color light emitted from these light sources. In addition to a normal display mode for displaying a color image, a display mode is provided in which display is performed by changing the display brightness and color tone by causing the light source to continuously emit light by the offset light control unit provided in the light source driving circuit 60. ing. In the both display modes, a switching operation to another display mode or a mixed operation of both display modes is possible.
[0032]
3 and 4 are timing charts for explaining three modes according to the driving method of the display device. FIG. 3 shows a case where the normal display mode is switched to the display mode only by the offset light control unit. FIG. 4 shows a case where the normal display mode is switched to the display mode using both the display light control unit and the offset light control unit.
[0033]
(Display mode by offset light control unit only)
In the timing chart shown in FIG. 3, each waveform conceptually indicates the light emission amount of each color light according to its height in addition to the light emission timing of the light sources 20R, 20G, and 20B. Further, the timing chart of the liquid crystal light valve 40 shows only the output timing of the image signal as in FIG.
[0034]
As shown in FIG. 3, when the display mode is switched in this driving method, each of the light sources 20R, 20G, and 20B does not emit light sequentially in time but continuously at a predetermined light emission amount (maximum light emission amount in FIG. 4). Lights up. In the example shown in FIG. 3, the light sources have the same output, the liquid crystal light valve 40 is irradiated with substantially white light, and the display image projected through the projection device 50 is between white and black. Gradation display.
[0035]
In the normal display mode, only one of the light sources 20R, 20G, and 20B is instantaneously emitting light, so that the display luminance cannot exceed the light emission amount of each light source. According to the method, since all the light sources 20R, 20G, and 20B emit light continuously for display, the display can be performed with extremely high luminance as compared with the normal display mode although it is a monochrome display. Therefore, it is possible to ensure the visibility of the display even in a scene where high brightness display is required such as outdoors in the daytime. In this way, if this driving method is provided, a solid-state light emitting device such as an LED having a lower light emission efficiency than that of UHP or the like can be used as a light source, and a high-luminance display can be performed as necessary. An available display device can be provided.
[0036]
(Display mode using display light control unit and offset light control unit in combination)
In the timing chart shown in FIG. 4, each waveform conceptually indicates the light emission amount of each color light according to its height in addition to the light emission timing of the light sources 20R, 20G, and 20B. Further, the timing chart of the liquid crystal light valve 40 shows only the output timing of the image signal as in FIG.
[0037]
As shown in FIG. 4, when the display mode is switched in this driving method, each of the light sources 20R, 20G, and 20B maintains time sequential light emission for performing image display, while maintaining a time other than its own light emission timing. Then, continuous light emission is performed at a predetermined output. For example, in the timing chart shown in FIG. 4, at the light emission timing of the light source 20 </ b> R, the light source 20 </ b> G and the light source 20 </ b> B emit light with a light emission amount that is about 1/3 of the maximum light emission amount. In this manner, by causing the other light sources to emit light at the light emission timing of one light source, a display with high luminance can be obtained although the chromaticity of the display is reduced. Therefore, even with this driving method, it is possible to display with high brightness as needed while using solid light emitting elements such as LEDs with low luminous efficiency as compared with UHP, etc. Possible display devices can be provided.
[0038]
In the present driving method, the light emission amount (offset amount) during continuous light emission of each of the light sources 20R, 20G, and 20B can be freely adjusted from zero to the maximum light emission amount of the light source. Therefore, the display brightness can be automatically controlled according to the manual operation of the user or the use environment of the display device.
[0039]
In addition, the light emission amount of each of the light sources 20R, 20G, and 20B can be controlled independently of each other. For example, when projecting an image in a bright yellow environment such as a restaurant, Among the light sources 20R, 20G, and 20B, by increasing the offset amount of the light source 20R and the light source 20G, the yellowness of the display image is increased, and an image display with a natural color tone can be performed even in the environment. Become.
[0040]
Furthermore, for example, when it is detected from the light measurement result of the light amount sensor 30 that the light emission amount of the light source 20R has decreased for some reason, the light sources 20G and 20B can be displayed by adding offset light. . In this case, although the image element displayed in red changes whitish, loss of display information due to a decrease in the amount of light can be prevented, so a display device that can withstand applications that require high reliability is provided. It becomes possible to do.
[0041]
(Circuit configuration example)
When the output of the offset light can be freely adjusted as in the present driving method, for example, it can be realized by providing the light source driving circuit 60 with the circuit shown in FIG. FIG. 5 is a circuit configuration diagram showing a main part of a light source driving circuit (light source control means) 60 to which the above driving method can be applied.
As shown in FIG. 5, the light sources 20R (20G, 20B) are connected to each other via a drive signal input unit 74, a signal superimposing circuit 73, a saturation circuit 72, and a drive signal output unit 71a (71b, 71c). An original drive waveform generated by the display light control unit (signal pattern storage unit 66, drive signal generation unit 67) is input to the signal superimposing circuit 73 from the drive signal input unit 74, while an offset light control unit (offset) The offset voltage generated by the light applying unit 68 and adjusted in output by the offset volume 75 is input. Then, the drive signal on which the two waveforms are superimposed is output to the saturation circuit 72. Then, after the peak level of the signal changed due to the waveform superposition by the signal superimposing circuit 73 is readjusted by the saturation circuit 72, each light source 20R (20G, 20B) is output from the drive signal output unit 71a (71b, 71c). A light source drive signal is output for each light source, and each light source performs a predetermined light emission operation based on the signal.
As described above, the driving method according to the present embodiment can be easily implemented by a relatively simple analog circuit shown in FIG.
[0042]
In the circuit diagram shown in FIG. 5, one offset volume 75 is connected to the signal superimposing circuit 73 of each light source, but this offset volume 75 is provided for each signal superimposing circuit 73. With such a configuration, it is possible to easily change the color balance of the display image. For example, when projecting an image in a bright yellow lighting environment such as a restaurant, the above light source Of the 20R, 20G, and 20B, by increasing the offset amount of the light source 20R and the light source 20G, the yellowness of the display image is increased, and an image display with a natural color tone can be performed even in the above environment.
[0043]
(Configuration example of display device)
FIG. 6 is a perspective view showing a front projector, which is a configuration example of the projection display device according to the embodiment. This front projector 1200 incorporates the optical system shown in FIG. 1 in a housing 1200 and projects and displays an image from a projection lens 1203 provided on the front surface. A control panel 1201 having a plurality of operation members (knob type volume, push buttons, etc.) 1202 is provided on the upper surface of the housing. By operating the operation member 1202, the output adjustment of the offset light can be performed, so that the display luminance can be freely adjusted.
[0044]
FIG. 7 is a perspective view showing a projector with a built-in telephone, which is another configuration example of the projector according to the embodiment. The projector 1300 incorporates the optical system shown in FIG. 1 and can project and display an image on a display unit 1301 provided on the front surface. In addition to operation buttons 1302, a reception unit 1303, and a transmission unit 1304 that provide functions as a mobile phone, operation buttons 1305U and 1305D, or a volume 1306 for adjusting the display brightness of an image projected on the display unit 1301 are provided. I have.
In the projector 1300, the display brightness of the image projected on the display unit 1301 can be freely adjusted by a push button operation using the operation buttons 1305U and 1305D or an operation of rotating the volume 1306. Accordingly, it is possible to easily obtain an appropriate luminance display.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram showing a projection display device (projector) which is an embodiment of a display device according to the present invention.
FIG. 2 is a timing chart in the display operation of the projection display device.
FIG. 3 is a timing chart of a mode according to a driving method of the display device.
FIG. 4 is a timing chart of a mode according to a method for driving a display device.
FIG. 5 is a circuit configuration diagram showing a main part of a light source driving circuit.
FIG. 6 is a perspective view illustrating a configuration example of a projection display apparatus according to an embodiment.
FIG. 7 is a perspective view illustrating a configuration example of a projection display apparatus according to an embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Illuminating device, 20R, 20G, 20B Light source 30 Light quantity sensor (photometry means), 40 Liquid crystal light valve (light modulation means), 50 Projection means (projection lens), 60 Light source drive circuit (light source control means), 66 Signal pattern storage Unit (display light control unit), 67 drive signal generation unit (display light control unit), 68 offset light application unit (offset light control unit)

Claims (10)

A plurality of light sources having different emission colors;
Light modulating means for modulating the color light emitted from the light source;
A display light control unit that sequentially emits each light source in time, and a light source control unit that includes an offset light control unit that continuously emits each light source at a predetermined output,
The light source control unit simultaneously performs light source control by the display light control unit and light source control by the offset light control unit, thereby causing each light source to emit light at a maximum light emission amount in time order, and A display device that emits light at the predetermined output at a light emission timing according to a maximum light emission amount .   The display device according to claim 1, wherein the light source control by the display light control unit and the light source control by the offset light control unit are switchable.   2. The display device according to claim 1, wherein the display light of the display device can be adjusted by causing the offset light control unit to emit the light sources at a predetermined output ratio. 3. Comprising photometric means capable of measuring the amount of light emitted from each light source;
4. The display device according to claim 1, wherein the light source control unit is capable of controlling an output of each light source based on a photometric result output from the photometric unit. 5. 5. The display according to claim 4, wherein the light source control unit is capable of adjusting a color balance between the color lights by adjusting an output of the light sources based on a photometric result of the photometry unit. apparatus.   6. The display device according to claim 4, wherein when the light emission amount of any of the plurality of light sources is equal to or less than a predetermined light amount, the offset light control unit continuously emits the light source with a predetermined output. .   The display device according to claim 1, wherein the offset light control unit is provided corresponding to each of the plurality of light sources.   A projector comprising: the display device according to claim 1; and a projection unit that projects light modulated by the light modulation unit. A plurality of light sources having different emission colors, a light modulation unit that modulates color light emitted from the light sources, a display light control unit that sequentially emits each light source, and each light source continuously emits light at a predetermined output. A light source control means including an offset light control unit, and a display device driving method comprising:
By simultaneously performing the light source control by the display light control unit and the light source control by the offset light control unit, each light source emits light at the maximum light emission amount sequentially in time, and the light emission timing by the maximum light emission amount of other light sources A display device driving method, wherein display is performed by emitting light at the predetermined output . Using a display device provided with photometric means capable of measuring the light emission amount of the light source,
10. The display device driving method according to claim 9 , wherein the color balance between the color lights output from the light sources is adjusted by the light source control unit based on a photometric result obtained by the photometry unit.

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