JP4947094B2 - Projector and optical apparatus - Google Patents

Description

  The present invention relates to a projector and an optical device, and more particularly to a projector using a solid light emitting element as a light source unit.

  The projector is a device that projects light (projection light) in accordance with an image signal supplied from an image supply device from a computer or the like and displays an image. It is known that a projector causes color unevenness in a projected image due to input / output characteristics of a display device, electrical characteristics of a signal processing circuit, optical characteristics of an optical system, and the like. A technique for eliminating color unevenness that occurs in an image display device or the like is proposed in Patent Document 1 shown below.

JP 2002-90880 A

  In recent years, it has been considered to use a solid-state light-emitting element such as a light-emitting diode element or a semiconductor laser in a light source section of a projector. The solid light-emitting element is small and lightweight, and its light emission luminance has been remarkably improved by recent developments. Therefore, it is suitable for a light source part of a projector. When the solid-state light emitting element is used as a light source unit, for example, a first light source unit that supplies red light (hereinafter referred to as “R light”) that is first color light, and green light (hereinafter referred to as “G light” that is second color light). The light source may be a second light source unit that supplies light, and a third light source unit that supplies blue light (hereinafter referred to as “B light”) that is third color light. The configuration having the first light source unit, the second light source unit, and the third light source unit has an advantage that the degree of freedom of arrangement of the light source unit is increased and a simple configuration can be obtained.

  Although the configuration using the first light source unit, the second light source unit, and the third light source unit and the plurality of light source units having different wavelength regions has the above-described advantages, brightness unevenness in any one of the light source units, that is, luminance If non-uniformity occurs, color unevenness occurs in the projected image. For example, it is assumed that non-uniform luminance, that is, so-called brightness unevenness occurs in a light source unit that supplies R light, and a portion where the R light is stronger than other regions is generated at the approximate center of the projected image on the screen. . In this case, the R light is emphasized from the G light and the B light in the region at the substantially central portion of the projected image, and a projected image with uneven color is obtained. In order to reduce variations in luminance among a plurality of light source units, a method is adopted in which the electrical state such as drive current and voltage of each light source unit is made constant. However, luminance non-uniformity generated in a single light source unit occurs even if the electrical state of the light source unit is constant.

  The non-uniformity of the luminance distribution of the light source unit changes with a temperature change. For this reason, when using a plurality of light source units having different wavelength regions, the color unevenness distribution of each color light from each light source unit changes with a temperature change. For example, it is assumed that the temperature of the light source unit that supplies the R light rises when a portion where the R light is emphasized is generated at substantially the center of the display image. In this case, for example, a change occurs such that the region where the R light is emphasized spreads around.

  In the conventional color unevenness elimination technology, it is difficult and problematic to eliminate the color unevenness in response to such a color unevenness change accompanying the temperature change of the light source unit. SUMMARY An advantage of some aspects of the invention is that it provides a projector and an optical apparatus that can reduce uneven color due to a temperature change of a light source unit and can provide a satisfactory full color image.

  In order to solve the above problems and achieve the object, in the present invention, a first light source unit that supplies first color light, a second light source unit that supplies second color light, and a third light source that supplies third color light are provided. And a first temperature detection unit that is disposed in the vicinity of the first light source unit, detects the temperature of the first light source unit, and is disposed in the vicinity of the second light source unit, and controls the temperature of the second light source unit. A second temperature detection unit for detecting, a third temperature detection unit arranged in the vicinity of the third light source unit for detecting the temperature of the third light source unit, the first light source unit, the second light source unit, and the A spatial light modulator that modulates light from the third light source unit according to an image signal, a projection lens that projects the light modulated by the spatial light modulator on a screen, the temperature of the first light source unit, and the first light source unit The relationship between the luminance distribution of the first color light from one light source unit, the temperature of the second light source unit, and the second light source A storage unit for storing a relationship between the luminance distribution of the second color light from the first light source and a relationship between the temperature of the third light source unit and the luminance distribution of the third color light from the third light source unit; Temperatures of the first light source unit, the second light source unit, and the third light source unit detected by the temperature detection unit, the second temperature detection unit, and the third temperature detection unit, respectively, are stored in the storage unit. Based on the relationship between the luminance distribution of the first color light, the second color light, and the third color light, the respective luminances of the first color light, the second color light, and the third color light on the screen And a control unit that controls the spatial light modulator so that the distribution is substantially uniform.

  By controlling the spatial light modulator so that the luminance distribution of each color light becomes substantially uniform based on the relationship between the temperature detected by each temperature detection unit and the luminance distribution, the color associated with the temperature change of each light source unit Unevenness can be reduced. In addition, by controlling the spatial light modulator based on the relationship between the temperature of each light source unit stored in the storage unit and the luminance distribution of each color light, the luminance of each color light is kept constant, and the color unevenness is reduced. A projector with a projected image can be obtained.

  In a preferred aspect of the present invention, the storage unit further stores a gradation correction value for correcting the gradation of the projected image, and the control unit includes the first temperature detection unit and the second temperature detection unit. The gradation correction value is changed and used based on the temperatures of the first light source unit, the second light source unit, and the third light source unit detected by the temperature detection unit and the third temperature detection unit, respectively. By doing so, it is desirable to control the spatial light modulation device so that the luminance distributions of the first color light, the second color light, and the third color light are substantially uniform on the screen.

  The spatial light modulator is controlled so that the luminance distribution of each color light becomes substantially uniform by changing the gradation correction value based on the temperature of each light source unit. The gradation correction value is a numerical value for converting the brightness level of each color light in order to accurately reproduce a desired natural color image. By reducing the color unevenness associated with the temperature change of each light source unit together with the gradation correction, a projector with less color unevenness and good color balance can be obtained.

  In a preferred aspect of the present invention, the storage unit further includes a temperature change amount of the first light source unit, a shift amount of the wavelength region of the first color light from the first light source unit, and a white balance. The relationship between the light amount shift amount of the first color light, the second color light, and the third color light for adjustment, the temperature change amount of the second light source unit, and the second color light from the second light source unit The relationship between the shift amount of the wavelength region, the light amount shift amount of the first color light, the second color light, and the third color light for adjusting the white balance, and the temperature change amount of the third light source unit, The relationship between the shift amount of the wavelength region of the third color light from the third light source unit and the light amount shift amount of the first color light, the second color light, and the third color light for adjusting white balance. And the control unit further stores the first A temperature change amount of the first light source unit, the second light source unit, and the third light source unit respectively detected by the degree detection unit, the second temperature detection unit, and the third temperature detection unit, and the storage unit The first light source unit, the second light source unit, and the second light source unit for adjusting white balance based on the relationship between the light amount shift amounts of the first color light, the second color light, and the third color light stored in It is desirable to control the light amount of the third light source unit.

  By controlling the light quantity of each color light from each light source part based on the relationship between the amount of temperature change detected by each temperature detection part and the light quantity shift amount of each color light for white balance adjustment, Accurate color images can be accurately reproduced. In addition, by controlling the light amount of each color light based on the relationship between the temperature change amount of each light source unit stored in the storage unit and the light amount shift amount of each color light, the white balance is kept constant, and the natural color image Can be accurately reproduced.

  Moreover, as a preferable aspect of the present invention, it further includes a light detection unit for detecting a luminance distribution of each of the first color light, the second color light, and the third color light, and the control unit includes the light Based on the respective luminance distributions of the first color light, the second color light, and the third color light detected by the detection unit, the respective luminance distributions of the first color light, the second color light, and the third color light. It is desirable to control the spatial light modulator so that is substantially uniform. The light detection unit detects the luminance distribution of each color light. The control unit controls the spatial light modulation device according to the luminance distribution of each color light so that the luminance distribution of each color light becomes substantially uniform. As a result, it is possible to obtain a projection image projector in which the luminance (brightness) of each color light is kept constant and the color unevenness is reduced.

  In a preferred aspect of the present invention, the optical system further includes a detection optical system that guides the first color light, the second color light, and the third color light projected from the projection lens onto the screen, respectively, to the light detection unit. It is desirable. By providing a detection optical system and guiding each color light projected on the screen from the projection lens to the light detection unit, the light detection unit can detect the luminance distribution on the screen of each color light. As a result, it is possible to obtain a projection image projector in which the luminance (brightness) of each color light is kept constant and the color unevenness is reduced.

  In a preferred aspect of the present invention, the first color light, the second color light, and the first color light that are provided in an optical path between the spatial light modulation device and the projection lens and are modulated by the spatial light modulation device. It is desirable to further include a light branching unit that branches three-color light into the direction of the projection lens and the direction of the light detection unit, and the light detection unit detects light branched by the light branching unit.

  By providing a light branching unit in the optical path between the spatial light modulation device and the projection lens and guiding the light branched by the light branching unit to the light detection unit, the light detection unit can control the luminance distribution of each color light. Can be detected. As a result, it is possible to obtain a projection image projector in which the luminance (brightness) of each color light is kept constant and the color unevenness is reduced.

  In a preferred aspect of the present invention, the light detection unit includes a first color light detection unit that detects the first color light, a second color light detection unit that detects the second color light, and the first color light detection unit. A third color light detection unit for detecting three-color light, provided in an optical path between the first light source unit and the spatial light modulator, and the first color light from the first light source unit Provided in the optical path between the second light source unit and the spatial light modulator, the first color light beam splitter branching in the direction of the spatial light modulator and the first color light detector. A second color light branching unit that branches the second color light from the second light source unit into a direction of the spatial light modulator and a direction of the second color light detection unit, and the third light source unit. The third color light from the third light source unit is provided in an optical path between the spatial light modulator and the spatial light modulator. A third color Hikari Mitsumochi branching section that branches to the direction of direction as the third color Hikari Mitsumochi unit, it is desirable to have.

  By providing a light branching unit in the optical path between the light source unit and the spatial light modulator and guiding the light branched by the light branching unit to the light detection unit, the light detection unit can control the luminance distribution of each color light. Can be detected. As a result, it is possible to obtain a projection image projector in which the luminance (brightness) of each color light is kept constant and the color unevenness is reduced.

  Moreover, as a preferable aspect of the present invention, the spatial light modulator further includes the first color light from the first light source unit, the second color light from the second light source unit, and the third light source unit. The tilt mirror device is composed of a movable mirror element that reflects each of the third color light from the projection lens in the direction of the projection lens or the direction other than the projection lens, and the light detection unit is It is desirable to detect light reflected in a direction other than the projection lens.

  By adopting a configuration that guides light reflected from the tilt mirror device in a direction other than the projection lens to the light detection unit, the light detection unit can detect the luminance distribution of each color light. Further, the light reflected in the direction of the light detection unit during image projection is light of a component that is unnecessary for forming a projected image. Accordingly, since the light forming the projection image is not reduced, a brighter projection image can be obtained than the configuration in which light is branched in the optical path of the projection light. As a result, it is possible to obtain a projector having a bright projection image with reduced color unevenness.

  Furthermore, in the present invention, a first light source unit that supplies the first color light, a second light source unit that supplies the second color light, a third light source unit that supplies the third color light, and the vicinity of the first light source unit. A first temperature detection unit disposed to detect a temperature of the first light source unit; a second temperature detection unit disposed near the second light source unit to detect a temperature of the second light source unit; and the first A light source from a third temperature detector that is disposed in the vicinity of the three light sources and detects the temperature of the third light source, and the light from the first light source, the second light source, and the third light source is used as an image signal. A spatial light modulator that modulates in response, an imaging lens that forms an image of light modulated by the spatial light modulator on a predetermined surface, the temperature of the first light source unit, and the first light from the first light source unit. The relationship between the luminance distribution of color light and the temperature distribution of the second light source unit and the luminance distribution of the second color light from the second light source unit. A storage unit that stores a relationship between the temperature of the third light source unit and the luminance distribution of the third color light from the third light source unit, the first temperature detection unit, the second temperature detection unit, and The temperatures of the first light source unit, the second light source unit, and the third light source unit respectively detected by the third temperature detection unit, and the first color light and the second color light stored in the storage unit And the spatial light so that the respective luminance distributions of the first color light, the second color light, and the third color light are substantially uniform on the predetermined surface based on the relationship with the luminance distribution of the third color light. It is possible to provide an optical device including a control unit that controls the modulation device. Accordingly, it is possible to obtain an optical device for a display image in which the luminance (brightness) of each color light is kept constant and the color unevenness is reduced.

1 is a diagram showing a schematic configuration of a projector according to a first embodiment of the invention. The block diagram of the structure for controlling each spatial light modulator. FIG. 6 is a diagram showing a schematic configuration of a projector according to a second embodiment of the invention. The block diagram of the structure for white balance adjustment. The figure which shows the wavelength characteristic of each color light. The figure which shows the chromaticity coordinate for demonstrating the change of white balance. FIG. 10 is a diagram showing a schematic configuration of a projector according to a third embodiment of the invention. The figure which shows the example of the luminance distribution detected by a photon detection part. The figure which shows the example of the luminance distribution detected by the photon detection part on A-A 'of FIG. The figure which shows the example which makes luminance distribution uniform using an interpolation value. The block diagram of the structure for stabilizing the light quantity of each color light. The figure which shows schematic structure of the projector which concerns on 4th Embodiment of this invention. The figure which shows schematic structure of the modification of 4th Embodiment. FIG. 10 is a diagram illustrating a schematic configuration of a projector according to a fifth embodiment of the invention. The figure which shows the diffraction element which diffracts the polarized light which has a specific vibration direction. The figure which shows schematic structure of the projector which concerns on 6th Embodiment of this invention. The figure which shows schematic structure of the 1st modification of 6th Embodiment. The figure which shows schematic structure of the 2nd modification of 6th Embodiment. FIG. 10 is a diagram illustrating a schematic configuration of a printer according to a seventh embodiment of the invention.

Embodiments of the present invention will be described below in detail with reference to the drawings.
(First embodiment)
FIG. 1 shows a schematic configuration of a projector according to a first embodiment of the present invention. The projector 100 includes a first light source unit 101R that supplies R light that is first color light, a second light source unit 101G that supplies G light that is second color light, and a third light source that supplies B light that is third color light. And a light source unit 101B. The first light source unit 101R, the second light source unit 101G, and the third light source unit 101B include light emitting diode elements (hereinafter referred to as “LEDs”) that are solid state light emitting elements.

  The R light from the first light source unit 101R enters the polarization conversion element 103R. The polarization conversion element 103R converts the R light into polarized light having a specific vibration direction, for example, p-polarized light. The R light that has undergone polarization conversion is incident on a spatial light modulator for R light 110R that is a spatial light modulator for first color light. The spatial light modulator for R light 110R is a transmissive liquid crystal display device that modulates R light according to an image signal. The spatial light modulator for R light 110R includes a liquid crystal panel 115R, a first polarizing plate 116R, and a second polarizing plate 117R.

  The first polarizing plate 116R transmits the R light converted into p-polarized light and makes it incident on the liquid crystal panel 115R. The liquid crystal panel 115R modulates p-polarized light according to an image signal and converts it into s-polarized light. The second polarizing plate 117R emits the R light converted into s-polarized light by the liquid crystal panel 115R. In this way, the R light spatial light modulator 110R modulates the R light from the first light source unit 101R. The R light converted into s-polarized light by the R light spatial light modulator 110R enters the cross dichroic prism 112.

  The G light from the second light source unit 101G enters the polarization conversion element 103G. The polarization conversion element 103G converts the G light into polarized light having a specific vibration direction, for example, s-polarized light. The polarization-converted G light is incident on the G light spatial light modulator 110G, which is the second color light spatial light modulator. The spatial light modulator 110G for G light is a transmissive liquid crystal display device that modulates G light according to an image signal. The G light spatial light modulator 110G includes a liquid crystal panel 115G, a first polarizing plate 116G, and a second polarizing plate 117G.

  The first polarizing plate 116G transmits the G light converted into s-polarized light and makes it incident on the liquid crystal panel 115G. The liquid crystal panel 115G modulates the s-polarized light according to the image signal and converts it into p-polarized light. The second polarizing plate 117G emits G light converted into p-polarized light by the liquid crystal panel 115G. Thus, the G light spatial light modulator 110G modulates the G light from the second light source unit 101G. The G light converted into p-polarized light by the G light spatial light modulator 110 </ b> G enters the cross dichroic prism 112.

  The B light from the third light source unit 101B enters the polarization conversion element 103B. The polarization conversion element 103B converts the B light into polarized light having a specific vibration direction, for example, p-polarized light. The polarization-converted B light is incident on the B light spatial light modulator 110B, which is the third color light spatial light modulator. The spatial light modulator 110B for B light is a transmissive liquid crystal display device that modulates B light according to an image signal. The B light spatial light modulator 110B includes a liquid crystal panel 115B, a first polarizing plate 116B, and a second polarizing plate 117B.

  The first polarizing plate 116B transmits the B light converted into p-polarized light and makes it incident on the liquid crystal panel 115B. The liquid crystal panel 115B modulates p-polarized light according to an image signal and converts it into s-polarized light. The second polarizing plate 117B emits the B light converted into s-polarized light by the liquid crystal panel 115B. In this way, the B light spatial light modulator 110B modulates the B light from the third light source unit 101B. The B light converted into the s-polarized light by the B light spatial light modulator 110B enters the cross dichroic prism 112.

  The cross dichroic prism 112 has two dichroic films 112a and 112b. The two dichroic films 112a and 112b are arranged orthogonal to the X shape. The dichroic film 112a reflects R light that is s-polarized light and transmits G light that is p-polarized light. The dichroic film 112b reflects B light that is s-polarized light and transmits G light that is p-polarized light. As described above, the cross dichroic prism 112 includes the R light modulated by the first color light spatial light modulation device 110R, the second color light spatial light modulation device 110G, and the third color light spatial light modulation device 110B. Synthesize G light and B light. The projection lens 130 projects the light combined by the cross dichroic prism 112 onto the screen 140.

  A first temperature detection unit 102R is disposed in the vicinity of the first light source unit 101R. The first temperature detection unit 102R detects the temperature of the first light source unit 101R, and outputs a signal corresponding to the detected temperature to the control unit 105. A second temperature detection unit 102G is disposed in the vicinity of the second light source unit 101G. The second temperature detection unit 102G detects the temperature of the second light source unit 101G, and outputs a signal corresponding to the detected temperature to the control unit 105. A third temperature detection unit 102B is disposed in the vicinity of the third light source unit 101B. The third temperature detection unit 102B detects the temperature of the third light source unit 101B, and outputs a signal corresponding to the detected temperature to the control unit 105.

  In FIG. 1, the first temperature detection unit 102R is adjacent to the first light source unit 101R, the second temperature detection unit 102G is adjacent to the second light source unit 101G, and the third temperature detection unit 102B is adjacent to the third light source unit 101B. Each is arranged. However, the arrangement of the temperature detection units is not limited to this position, and can be changed as appropriate as long as the temperature of each light source unit can be detected.

  The storage unit 107 stores the relationship between the temperature of each of the light source units 101R, 101G, and 101B and the luminance distribution of each color light as data. The control unit 105 is based on the relationship between the temperature of each light source unit detected by each of the temperature detection units 102R, 102G, and 102B and the luminance distribution of the R light, G light, and B light stored in the storage unit 107. Thus, the color light spatial light modulators 110R, 110G, and 110B are controlled.

  FIG. 2 shows a block diagram of a configuration for controlling each spatial light modulator. Each spatial light modulation device is controlled based on the relationship between the temperature of each light source unit detected by each temperature detection unit and the luminance distribution of each color light stored in the storage unit 107. Hereinafter, control of the R light spatial light modulator 110R will be described as a representative example. The first temperature detection unit 102R detects the temperature of the first light source unit 101R and outputs a detection result. The signal output from the first temperature detection unit 102R is amplified. Next, the relationship between the temperature of the first light source unit 101R stored in the storage unit 107 and the luminance distribution of the R light (indicated as “temperature table” in FIG. 2) is referred to. Then, the control unit 105 compares the detection result with the temperature table data. The control unit 105 outputs a signal after the comparison calculation. The driving of the spatial light modulator for R light 110 </ b> R is controlled by a signal from the control unit 105.

  In this way, the spatial light modulation device 110R for R light uses the brightness of the R light on the screen 140 based on the relationship between the temperature of the first light source unit 101R stored in the storage unit 107 and the luminance distribution of the R light. The distribution is controlled to be substantially uniform. Similarly to the R light spatial light modulator 110R, the G light spatial light modulator 110G and the B light spatial light modulator 110B are controlled so that the luminance distribution of the G light and the B light is substantially uniform on the screen 140. Is done.

  Thereby, there is an effect that the color unevenness accompanying the temperature change of each light source part 101R, 101G, 101B can be reduced. Each color light is controlled by controlling each spatial light modulator 110R, 110G, 110B based on the relationship between the temperature of each light source unit 101R, 101G, 101B stored in the storage unit 107 and the luminance distribution of each color light. The luminance distribution of the is kept constant. Thereby, there is an effect that it is possible to obtain the projector 100 with a projected image with reduced color unevenness.

  Further, it is desirable that the storage unit 107 further stores a gradation correction value for correcting the gradation of the projected image. In this case, the control unit 105 changes and uses the gradation correction value based on the temperature of each light source unit. Each spatial light modulator is controlled by using a modified tone correction value. Here, the gradation correction value is a numerical value for converting the brightness level of each color light in order to accurately reproduce a natural color image, and is a so-called gamma correction value. Based on the relationship between the temperature of each light source unit 101R, 101G, 101B detected by each temperature detection unit 102R, 102G, 102B and the luminance distribution of each color light, the gradation correction value may be appropriately changed and used. it can.

  By changing the gradation correction value based on the temperature of each light source unit 101R, 101G, and 101B, each spatial light modulator 110R, 110G, and 110B can make the luminance distribution of each color light substantially uniform. Be controlled. In each of the spatial light modulators 110R, 110G, and 110B, color unevenness due to temperature change of the light source unit is reduced together with gradation correction. Thereby, there is an effect that it is possible to obtain the projector 100 with less color unevenness and good color balance.

  Note that the relationship between the temperature of each of the light source units 101R, 101G, and 101B and the luminance distribution of each color light can be stored in the storage unit 107 in advance when the projector 100 is shipped, for example. Thereby, there is an effect that it is possible to always perform a stable color unevenness reduction process. Further, at the time of shipment, the temperature may be detected using another means that is more precise than the temperature detection using the temperature detection units 102R, 102G, and 102B of the projector 100. Thereby, the storage unit 107 has an effect that the uneven color can be surely reduced by storing more precise data on the relationship between the temperature of each light source unit and the luminance distribution of each color light.

  The projector 100 according to this embodiment is a projector using a so-called three-plate liquid crystal light valve having three liquid crystal display devices as a spatial light modulator. However, the present invention is not limited to this, and a configuration having one liquid crystal display device may be employed. Furthermore, the present invention is not limited to the case of using a transmissive liquid crystal display device, and can be applied to both a projector using a reflective liquid crystal display device and a projector using another light valve.

(Second Embodiment)
FIG. 3 shows a schematic configuration of a projector according to the second embodiment of the invention. The same parts as those in the first embodiment are denoted by the same reference numerals, and redundant description is omitted. Similar to the projector 100 according to the first embodiment, the projector 300 according to the present embodiment includes temperature detection units 102R, 102G, and 102B. The LED constituting the light source unit described later has a characteristic that the wavelength region of the emitted light shifts in response to a change in environmental temperature. When the wavelength region of the emitted light shifts, the ratio of each light quantity for obtaining white also changes. For this reason, the white balance is lost due to the wavelength shift due to the temperature change of the light source unit. In view of this point, the projector 300 according to the present embodiment has each light source unit driving circuit based on the relationship between the temperature change amount of each light source unit and the light amount shift amount of each color light for white balance adjustment. It is characterized by controlling.

  The projector 300 includes a first light source unit 301R that supplies R light as first color light, a second light source unit 301G that supplies G light as second color light, and a third light source that supplies B light as third color light. And a light source unit 301B. The first light source unit 301R, the second light source unit 301G, and the third light source unit 301B include LEDs that are solid-state light emitting elements. The first light source unit 301R is driven by a first light source unit drive circuit 304R. The second light source unit 301G is driven by a second light source unit drive circuit 304G. The third light source unit 301B is driven by a third light source unit drive circuit 304B.

  The storage unit 307 includes the temperature change amount of each light source unit 301R, 301G, 301B, the shift amount of the wavelength region of each color light from each light source unit, and the light amount shift amount of each color light for adjusting the white balance. Remember the relationship. Based on the relationship between the temperature change amount of each light source unit detected by each temperature detection unit 102R, 102G, 102B and the light amount shift amount of each color light stored in the storage unit 307, the control unit 305 The light source unit driving circuits 304R, 304G, and 304B are controlled by the procedure described later.

  FIG. 4 shows a block diagram of a configuration for controlling each of the light source unit driving circuits 304R, 304G, and 304B. Each light source unit drive circuit 304R, 304G, 304B is controlled based on the relationship between the temperature change amount of each light source unit and the light amount shift amount of each color light stored in the storage unit 307. Each temperature detection unit 102R, 102G, 102B detects the temperature of each light source unit 301R, 301G, 301B, and outputs a signal according to the detected temperature to the wavelength shift amount calculation unit of the control unit 305. In the wavelength shift amount calculation unit, for each color light, the relationship between the temperature change amount of each light source unit 301R, 301G, 301B stored as data in the storage unit 307 and the shift amount of the wavelength region of each color light (in FIG. 4). , Referred to as “temperature-wavelength conversion data”). Thereby, the control unit 305 calculates the wavelength shift amount for each color light.

  The wavelength shift amount calculation unit outputs a signal corresponding to the calculated wavelength shift amount to the light amount calculation unit. In the light amount calculation unit, for each color light, the relationship between the wavelength shift amount stored as data in the storage unit 307 and the light amount shift amount of each color light for white balance adjustment (in FIG. Referred to as “converted data”). As a result, the control unit 305 calculates a light amount shift amount for each color light.

  The control unit 305 outputs a signal corresponding to the calculated light amount shift amount to each of the light source unit drive circuits 304R, 304G, and 304B. Each of the light source unit driving circuits 304R, 304G, and 304B is controlled by a signal corresponding to the light amount shift amount from the control unit 305. In this way, the control unit 305 determines each of the temperature change amounts detected by the temperature detection units 102R, 102G, and 102B and the light amount shift amount of each color light stored in the storage unit 307. The light source unit drive circuits 304R, 304G, and 304B are controlled.

  Next, white balance adjustment by the control of the control unit 305 will be described. FIG. 5 shows the wavelength characteristics of each color light LED with the horizontal axis representing wavelength (unit: nm) and the vertical axis representing intensity (arbitrary unit). The projector 300 projects the color light having the respective wavelength characteristics shown in FIG. The observer integrates and recognizes light having each wavelength characteristic of R light, G light, and B light. All colors are obtained by additive mixing of R light, G light and B light. As a result, a full-color projection image can be obtained on the screen 140.

  FIG. 6 shows an xy chromaticity diagram. All colors are represented on a three-dimensional space by displaying coordinates of R, G, B intensity ratios (stimulus values) (RGB color system). The stimulus value of each color light is expressed as a relative ratio to the luminance of each color required when the mixed color looks white at a color temperature of 4800K. The XYZ display system is obtained by appropriately converting the coordinate axes so that all chromaticities can be expressed as positive values from the three-dimensional space of the RGB color system. An xy chromaticity diagram is obtained by projecting an XYZ display system, which is a three-dimensional space, onto an XY plane. In the xy chromaticity diagram, only the hue and the saturation are represented by excluding the information relating to the lightness among the color elements. The point R shown in FIG. 6 is the R light from the R light LED, the point G is the G light from the G light LED, the point B is the B light from the B light LED, and the point W is the white balance point. .

  The wavelength characteristic of the LED shifts to the longer wavelength side in response to an increase in environmental temperature, particularly the temperature of the light emitting chip portion. The wavelength characteristics of the LED for R light are about 0.05 nm when the temperature of the light emitting chip portion is raised by 1 ° C., and the wavelength characteristics of the LEDs for G light and B light are about 0.04 nm long wavelength when the temperature is raised by 1 ° C. Shift to the side. As an example, let us consider a case where the temperature of the third light source unit 301B having the B light LED rises. As indicated by the arrow I in FIG. 5 and the arrow C in FIG. 6, the wavelength characteristics of the B light from the B light LED shift to the longer wavelength side in response to the temperature rise of the B light LED. When the wavelength characteristic of B light from the B light LED shifts to the longer wavelength side, the white balance point W shown in FIG. 6 shifts to a point W ′. By shifting the white balance point to W ′, white cannot be obtained with the light quantity balance of each color light indicated by the point W.

  The storage unit 307 stores the temperature change amount of the third light source unit 301B, the wavelength shift amount of the B light, and the light amount shift amounts of the R light, the G light, and the B light for adjusting the white balance. Yes. Based on the relationship between the temperature change amount of the third light source unit 301B and the light amount shift amounts of the R light, G light, and B light stored in the storage unit 307, the control unit 305 determines whether the white balance is the original position W. The light source unit drive circuits 304R, 304G, and 304B are controlled so that Specifically, by increasing the amount of B light (arrow E) and further increasing R light or G light (arrow D), the chromaticity coordinates of white are returned from the point W ′ to the point W. .

  In the present embodiment, as described above, each light source is based on the relationship between the temperature change amount detected by each temperature detection unit 102R, 102G, 102B and the light amount shift amount of each color light for white balance adjustment. The amount of light of each color from the units 301R, 301G, and 301B is controlled. As a result, the color unevenness associated with the temperature change of each of the light source units 301R, 301G, and 301B is reduced, and at the same time, an effect that a natural color image can be accurately reproduced. Further, by controlling the light amount of each color light from each light source unit based on the relationship between the temperature of each light source unit stored in the storage unit 307 and the light amount shift amount of each color light, the white balance is kept constant and natural As a result, it is possible to obtain a projection image that accurately reproduces a color image.

  Note that, similarly to the projector 100 according to the first embodiment, the projector 300 according to this embodiment is configured so that the luminance distribution of each color light becomes substantially uniform on the screen 140 as the temperature of each of the light source units 301R, 301G, and 301B changes. Further, the spatial light modulators 110R, 110G, and 110B for each color light may be controlled. Thereby, while performing exact color reproduction, there exists an effect that the color nonuniformity accompanying the temperature change of each light source part can be reduced.

(Third embodiment)
FIG. 7 shows a schematic configuration of a projector according to the third embodiment of the invention. The same parts as those in the first embodiment are denoted by the same reference numerals, and redundant description is omitted. A feature of the projector 700 according to the third embodiment is that it includes a light detection unit. The projector 700 includes a first light source unit 701R that supplies R light as first color light, a second light source unit 701G that supplies G light as second color light, and a third light source that supplies B light as third color light. A light source unit 701B. The first light source unit 701R, the second light source unit 701G, and the third light source unit 701B have LEDs that are solid-state light emitting elements. The first light source unit 701R is driven by a first light source unit driving circuit 704R. The second light source unit 701G is driven by a second light source unit drive circuit 704G. The third light source unit 701B is driven by a third light source unit drive circuit 704B.

  The color lights supplied from the light source units 701R, 701G, and 701B are transmitted through the polarization conversion elements 103R, 103G, and 103B, and then enter the spatial light modulators 110R, 110G, and 110B for the color lights. Each of the color light spatial light modulators 110R, 110G, and 101B modulates light from each of the light source units 701R, 701G, and 701B according to an image signal. The cross dichroic prism 112 combines the R light, G light, and B light modulated by the spatial light modulators 110R, 110G, and 110B for the respective color lights. The projection lens 130 projects the light combined by the cross dichroic prism 112 onto the screen 140.

  The projector 700 has a detection optical system 708 composed of a single lens in the vicinity of the exit side end face of the projection lens 130. The detection optical system 708 has a function of guiding R light, G light, and B light projected from the projection lens 130 onto the screen 140 to the light detection unit 702, respectively. The light detection unit 702 detects the luminance distribution of each of R light, G light, and B light. The detection timing and procedure of the luminance distribution of each color light will be described later. Based on the luminance distributions of the R light, G light, and B light detected by the light detection unit 702, the control unit 705 sets each color so that the luminance distributions of the R light, G light, and B light are substantially the same. The spatial light modulators 110R, 110G, and 110B for light are controlled. As a result, the brightness of each color light can be kept constant, and the projector 700 with reduced color unevenness can be obtained. The storage unit 707 will be described later.

  In addition to the above-described configuration, the color light spatial light modulators 110R, 110G, and 110B may be controlled in the same manner as the projector 100 of the first embodiment. Each color light spatial light modulator is controlled so that the luminance distribution of each color light is substantially uniform on the screen 140 based on the relationship between the temperature of each light source and the luminance distribution of each color light. As a result, there is an effect that the color unevenness accompanying the temperature change of each light source unit can be reduced. Further, the position of the detection optical system 708 is not limited to the vicinity of the exit side end face of the projection lens 130, and may be any position that can guide the light projected on the screen 140 to the light detection unit 702.

  Hereinafter, based on the luminance distribution of each color light detected by the light detection unit 702, a control procedure for making the luminance distribution of each color light substantially the same will be described. First, the procedure will be described using R light as a representative example. When the luminance distribution of R light is detected, the first light source unit 701R is turned on, and the second light source unit 701G and the third light source unit 701B are turned off. Note that the G light and B light may be blocked by a shutter mechanism or the like while the second light source unit 701G and the third light source unit 701B are turned on. Further, the G light spatial light modulator 110G and the B light space are arranged so that the G light and the B light are not projected onto the screen 140 while the second light source unit 701G and the third light source unit 701B are turned on. The light modulation device 110B may be driven. For example, consider a case in which the R light spatial light modulator 110R is driven so that only the R light supplied from the first light source unit 701R is projected onto the screen 140 with the highest luminance gradation over all pixels. At this time, only the R light is projected on the entire screen 140 with the maximum luminance. The detection optical system 708 guides the R light projected on the screen 140 to the light detection unit 702.

  FIG. 8 shows an example of the luminance distribution detected by the light detection unit 702 when the R light is projected onto the screen 140 with the maximum luminance over all pixels. In the light detection unit 702, for example, CCDs, CMOS sensors, or photodiode arrays are arranged in a matrix of 4 rows and 7 columns.

  Each sensor element detects the R light projected on the screen 140 and guided by the detection optical system 708. In each sensor element, the area ARA1 indicates a state with the highest detected brightness, the area ARA4 indicates a state with the lowest detected brightness, and the areas ARA2 and ARA3 indicate a state of intermediate brightness between them. The luminance distribution on the screen 140 is distributed with a resolution corresponding to the number of pixels of each color light spatial light modulator 110R, 110G, 110B. On the other hand, on the light detection unit 702, the luminance distribution is detected with a resolution (4 × 7 in the case of FIG. 8) corresponding to the number of sensor elements.

  FIGS. 9A and 9B are graphs showing gradation histograms detected by the sensor elements on A-A ′ in FIG. 8. The vertical axis of the graph shown in FIG. 9 indicates the gradation level of the R light, and the horizontal axis indicates the position of the sensor element on A-A ′ of the light detection unit 702. As shown in FIG. 9A, the gradation level of the R light detected by each sensor element ranges from 248 gradations to 255 gradations.

  The control unit 705 drives the spatial light modulator for R light 110R so that the pixel of the spatial light modulator for R light 110R corresponding to AA ′ has 248 gradations which is the lowest value among the detection values. To control. FIG. 9B shows a portion of the pixel of the spatial light modulation device 110R for R light that is hatched so as to obtain 248 gradations for a pixel corresponding to a sensor that exhibits gradations of 248 gradations or more. Decrease the brightness level corresponding to. Thereby, the luminance distribution of the R light can be made substantially uniform for the pixels corresponding to the sensor elements on A-A ′. The same processing is performed not only on the pixels corresponding to the sensors on A-A ′ but also on all the pixels of the R light spatial light modulator 110 </ b> R. Thereby, the control unit 705 can make the luminance distribution of the R light constant for all the pixels of the spatial light modulator for R light 110R.

  In the projector 700 of the present embodiment, the R light spatial light modulator 110R is driven so that all pixels have the highest luminance for the R light, and the luminance distribution of the R light is controlled using the luminance distribution at this time. Yes. Since the R light spatial light modulator 110R is driven so as to obtain the maximum luminance, it is impossible to make the gradation higher than the detected luminance for all the pixels. For this reason, it is desirable to control the spatial light modulator for R light 110 </ b> R so that it is unified with the lowest gradation among the detection values of each sensor element.

  In order to detect the luminance unevenness of the R light, as described above, the R light spatial light modulator 110R is driven so as to project the R light onto the screen 140 with the highest luminance. When detecting the luminance distribution of the R light, the G light spatial light modulation device 110G and the B light spatial light modulation device 110B are driven so as not to project the G light and the B light onto the screen 140. Further, the G light and B light may be blocked by a shutter mechanism or the like. Further, the first light source unit 701R may be turned on and the second light source unit 701G and the third light source unit 701B may be turned off.

  As described above, the control unit 705 controls the R light spatial light modulation device 110R based on the luminance distribution of the R light detected by the light detection unit 702. Similarly to the R light, the control unit 705 also controls the G light spatial light modulators 110G and B light based on the respective luminance distributions of the G light and B light detected by the light detection unit 702. The spatial light modulation device 110B is controlled. Thereby, the luminance distribution of the R light, the G light, and the B light can be made uniform, and the uneven color of the projected image can be reduced.

  In addition, a storage unit may be provided in the projector 700, and control information data of each color light spatial light modulation device that makes the luminance distribution uniform may be stored in advance. For example, when the projector 700 is shipped, the luminance distribution of each color light is detected in the same procedure as described above. Then, the color light spatial light modulators are controlled so that the luminance distributions of the R light, G light, and B light are uniform. The storage unit stores control information data of each color light spatial light modulation device that makes the luminance distribution of each color light uniform. The control unit 705 can control each color light spatial light modulator 110R, 110G, 110B based on the control information data. As a result, it is possible to obtain a projection image that always has little color unevenness and uniform brightness.

  In addition, when the projector 700 is shipped, light detection may be performed using another means that is more precise than the light detection using the light detection unit 702 included in the projector 700. As a result, the storage unit stores the more precise data regarding the control of the spatial light modulation device for each color light to make the luminance distribution of each color light uniform, thereby achieving an effect of reliably reducing color unevenness. .

  The timing at which the light detection unit 702 detects the luminance distribution of each color light can be set as appropriate. For example, it is possible to detect the luminance distribution of each color light by the light detection unit 702 when the light source emits light, and then perform an interval of several minutes when the image is not displayed. As a result, it is possible to obtain a projection image with little color unevenness.

  Next, another control example in which the luminance distribution of each color light is made substantially the same according to the luminance distribution of each color light detected by the light detection unit 702 will be described. The size of each sensor element of the light detection unit 702 illustrated in FIG. 8 corresponds to the size of a plurality of pixels of the spatial light modulation device. For example, the area of 100 × 100 pixels of the spatial light modulator corresponds to one sensor element area. In the above description using FIG. 9, the spatial light modulation device is controlled to be substantially the same for all the pixels corresponding to one sensor element. In this control example, a case is considered where adjacent sensors among the sensors included in the light detection unit 702 have different detection values.

  For example, the gradation level detected by the sensor element 702a shown in FIG. 8 is 255 gradations, the gradation level detected by the sensor element 702b adjacent to the sensor element 702a is 253 gradations, and the detected values are two gradations. (See FIG. 9). In order to uniformly set the gradation level of all the pixels to 248 gradations, the spatial light modulation device 110R for R light controls the gradation corresponding to the sensor element 702b by reducing the gradation by 7 gradations in the pixel corresponding to the sensor element 702a area. The pixel to be controlled is lowered by 5 gradations. At this time, in the pixel corresponding to the boundary line portion between the sensor element 702a and the sensor element 702b, the gradation level subtracted by the control has a difference of two gradations. For this reason, in the projected image, a stepwise difference occurs in the luminance level at a portion corresponding to the boundary line portion between the sensor element 702a and the sensor element 702b.

  Therefore, a control example for preventing the occurrence of a level difference in luminance level by the control unit 705 will be described. The detection value (gradation level) of each sensor element of the light detection unit 702 is applied to the pixel corresponding to the center of the area of the sensor element. When the detection values of adjacent sensor elements are different, an interpolation value is calculated from the pixel corresponding to the center of the sensor element region to the pixel corresponding to the boundary line of the sensor element, and the R light spatial light modulator 110R. To control.

  For example, the detection result shown in FIG. 9 indicates that the gradation level of the pixel corresponding to the center of the sensor element 702a is 255 gradations, and the gradation level of the pixel corresponding to the center of the sensor element 702b is 253 gradations. Fit the value. For a pixel between the pixel corresponding to the center of the sensor element 702a and the pixel corresponding to the center of the sensor element 702b, 255 gradations of the pixel in the center of the sensor element 702a and the sensor A value obtained by interpolating with the value of 253 gradations of the pixel in the center of the region of the element 702b is applied. For pixels between the pixel corresponding to the center of the area of the sensor element 702a and the pixel corresponding to the center of the area of the sensor element 702b, the calculated interpolation value is used for the spatial light modulator for R light 110R. Take control. By using the interpolation value, it is possible to prevent a luminance step from occurring in a portion corresponding to the boundary portion between the sensor 702a and the sensor b in the projected image.

  FIG. 10 shows the interpolated gradation level. For the sensor elements on A-A ′ shown in FIG. 8, a process of subtracting a predetermined gradation level so as to obtain a constant gradation is performed using the interpolation value H based on the luminance distribution shown in FIG. 9. In FIG. 10, the gradation level that is reduced to 248 gradations, which is a constant gradation level, is represented by the hatched portion. By controlling the spatial light modulator using the interpolation value H, it is possible to prevent the occurrence of a luminance step. As a result, the luminance unevenness is reduced and a projection image with little color unevenness can be obtained. For the calculation of the interpolation value H, for example, any of linear approximation, quadratic curve approximation, and spline interpolation may be used.

  In FIG. 8, the sensor included in the light detection unit 702 is provided as seven in the long side direction and four in the short side direction of the light irradiation surface of the light detection unit 702, and the total quantity is illustrated as 28. The number of sensors is not limited to this. The number of sensors can be set as appropriate from a minimum of two to a maximum of the number of pixels of the spatial light modulator. Since the luminance distribution can be detected more accurately as the number of sensors is larger, color unevenness can be reliably reduced.

  Further, the projector 700 according to the present embodiment may be used by appropriately changing the gradation correction value based on the detection value by the light detection unit 702, similarly to the projector 100 according to the first embodiment. By changing and using the gradation correction value based on the detection value by the light detection unit 702, spatial light modulation is performed so that the luminance distribution of the R light, G light, and B light on the screen 140 is substantially uniform. Control the device. As a result, it is possible to obtain a projector with little color unevenness and good color balance. Furthermore, instead of using the gradation correction value by changing it, the spatial light modulator may be controlled based on the detection value by the light detection unit 702 separately from the gradation correction. In this case, the control based on the detection value by the light detection unit 702 may be performed before or after the gradation correction.

  Next, as a modification of the third embodiment, a configuration for stabilizing the light amount of each light source unit by the detection value from the light detection unit 702 will be described. FIG. 11 shows a block diagram of a configuration for stabilizing the light amounts of the respective color lights supplied from the first light source unit 701R, the second light source unit 701G, and the third light source unit 701B based on the detection value by the light detection unit 702. Detection values from all the sensor elements included in the light detection unit 702 are added by the addition unit and output to the control unit 705. A value obtained by adding the detection values from all the sensor elements is a light amount value of the color light generated from any one of the light source units. In the comparison unit, the control unit 705 compares the addition result output from the addition unit with the light amount reference value of each light source unit stored in the storage unit 707 to calculate a difference. The control unit 705 controls each light source unit drive circuit 704R, 704G, 704B based on the comparison result calculated by the comparison unit.

  The light quantity reference value of each light source unit can be stored in the storage unit 707 when the projector 700 is shipped, for example. Thus, the gradation level corresponding to the area from each sensor element is not limited, and an integrated value obtained by adding all these gradation levels can also be used. Thereby, the light quantity of each color light from each light source part is stabilized, and there is an effect that a projector 700 with good color balance can be obtained. Further, the timing for stabilizing the light amount of the light source unit can be changed as appropriate, similarly to the control of the spatial light modulator. Furthermore, by stabilizing the light amount of each color light in combination with the control of the spatial light modulator for each color light, there is an effect that the color balance can be improved and the color unevenness of the projected image can be reduced.

  In addition, the projector 700 of the present embodiment has three liquid crystal display devices as spatial light modulation devices. However, the present invention is not limited to this, and the projector 700 may be configured to include one liquid crystal display device. In the case of having one liquid crystal display device, only a single light source unit, for example, only the first light source unit 701R is turned on, and the second light source unit 701G and the third light source unit 710B are turned off. In the meantime, the liquid crystal display device is driven so that the gradation of the R light is the same for all the pixels. The light detection unit 702 detects the R light projected on the screen 140 and controls the liquid crystal display device so that the luminance distribution becomes substantially uniform. The liquid crystal display device is similarly controlled for the G light and the B light. Thereby, there is an effect that the projector 700 with reduced color unevenness can be obtained.

  In the case of having one liquid crystal display device, each light source unit is sequentially turned on in one frame period. For example, one frame of an image is composed of a subframe that turns on the first light source unit 701R, a subframe that turns on the second light source unit 701G, and a subframe that turns on the third light source unit 701B. A full color image can be obtained by sequentially displaying the R light subframe, the G light subframe, and the B light subframe. Here, in synchronization with each subframe, which is the lighting period of each light source unit, the light detection unit 702 can detect each color light in one frame period. Further, it is possible to detect the light quantity of the three color light divided into a plurality of frames without detecting all the three color lights in one frame period. For example, in the first frame, the light detection unit 702 detects R light and controls driving of the liquid crystal display device with respect to R light. The G light is detected and the above control is performed in the next frame. Finally, the B light may be detected and controlled in the next frame after the G light control. Such control has an effect that color unevenness can be surely reduced when the detection speed of each sensor element is low or when the signal processing speed is low.

(Fourth embodiment)
FIG. 12 shows a schematic configuration of a projector according to the fourth embodiment of the invention. The same parts as those in the first embodiment and the third embodiment are denoted by the same reference numerals, and redundant description is omitted. Similar to the projector 700 according to the third embodiment, the projector 1200 according to the present embodiment includes a light detection unit 702 for detecting each luminance distribution of R light, G light, and B light. The projector 1200 is characterized by having a light branching unit.

  The cross dichroic prism 112 synthesizes and emits the modulated light from the color light spatial light modulators 110R, 110G, and 110B. The combined light is incident on a beam splitter 1220 that is an optical branching unit. The beam splitter 1220 is provided in the optical path between the color light spatial light modulators 110R, 110G, and 110B and the projection lens 130 via the cross dichroic prism 112.

  The beam splitter 1220 has a light beam splitting surface 1220a. The light beam splitting surface 1220a splits R light, G light, and B light at a predetermined intensity ratio regardless of the polarization direction. For example, the light splitting surface 1220a transmits 90% of incident R light, G light, and B light and reflects 10%. The light reflected from the light splitting surface 1220 a is bent 90 degrees in the optical path and travels in the direction of the light detection unit 702. In this manner, the beam splitter 1220 converts the R light, G light, and B light modulated by the respective color light spatial light modulators 110R, 110G, and 110B into the direction of the projection lens 130 and the direction of the light detection unit 702, respectively. Branch.

  The light detection unit 702 detects the luminance distribution of each of the R light, the G light, and the B light from the light branched by the beam splitter 1220. For example, when the luminance distribution of R light is detected, the first light source unit 701R is turned on, and the second light source unit 701G and the third light source unit 701B are turned off. Alternatively, the G light spatial light modulation device 110G and the B light spatial light modulation device 110B may be controlled to be shielded from light while all the light source units 701R, 701G, and 701B are turned on. In this way, the luminance distribution of only R light can be detected. Similarly, when detecting the luminance distribution of G light and B light, only desired color light is made incident on the light detection unit 702. Then, the control unit 1205 controls the color light spatial light modulators 110R, 110G, and 110B so that the luminance distribution of each color light detected by the light detection unit 702 is substantially uniform. With the beam splitter 1220 configured to guide the branched light to the light detection unit 702, the light detection unit 702 can detect the luminance distribution of each color light. As a result, the luminance (brightness) of each color light can be kept constant, and the projector 1200 with reduced color unevenness can be obtained.

(Modification of the fourth embodiment)
FIG. 13 shows a schematic configuration of a modified example of the fourth embodiment. The same parts as those of the projector 1200 are denoted by the same reference numerals, and redundant description is omitted. The projector 1300 has a diffractive element 1320 as a light branching portion on the exit side of the cross dichroic prism 112. The cross dichroic prism 112 synthesizes the light modulated by the spatial light modulators 110R, 110G, and 110B for each color light, and enters the diffraction element 1320 side. The diffraction element 1320 is provided in the optical path between the color light spatial light modulators 110R, 110G, and 110B and the projection lens 130 via the cross dichroic prism 112. For the diffraction element 1320, for example, a blazed diffraction grating can be used.

  The diffraction element 1320 diffracts R light, G light, and B light at a predetermined intensity ratio regardless of the polarization direction. For example, the diffraction element 1320 transmits 90% of incident R light, G light, and B light in the direction of the projection lens 130 (0th order light), and diffracts 10% in directions other than the projection lens 130 (± 1 next time). Fold light). The light diffracted by the diffraction element 1320 enters the light detection unit 702.

  In this way, the diffraction element 1320 converts the R light, G light, and B light modulated by the respective color light spatial light modulators 110R, 110G, and 110B into the direction of the projection lens 130 and the direction of the light detection unit 702, respectively. Branch. The light detection unit 702 detects the light branched by the diffraction element 1320. The control unit 1305 controls the color light spatial light modulators 110R, 110G, and 110B so that the luminance distribution of the color lights detected by the light detection unit 702 is substantially uniform. When the diffractive element 1320 which is a light branching portion is configured to guide the branched light to the light detection unit 702, the light detection unit 702 can detect the luminance distribution of each color light. As a result, the brightness of each color light can be kept constant, and the projector 1300 with reduced color unevenness can be obtained.

(Fifth embodiment)
FIG. 14 shows a schematic configuration of a projector according to the fifth embodiment of the invention. The same parts as those in the first embodiment and the third embodiment are denoted by the same reference numerals, and redundant description is omitted. A projector 1400 according to the present embodiment is similar to the projectors 1200 and 1300 described in the fourth embodiment, and includes a light detection unit for detecting the luminance distribution of each of R light, G light, and B light, and a light detection unit. And a light branching part that branches light in the direction of. A feature of the projector 1400 according to the present embodiment is that, for each color light, a light branching unit is provided in an optical path between each light source unit and each color light spatial light modulator.

  The R light supplied from the first light source unit 701R will be described as a representative example. The R light from the first light source unit 701R enters the polarization conversion element 103R. The polarization conversion element 103R converts the incident R light into a specific polarization direction, for example, p-polarized light. Here, due to the optical characteristics of the polarization conversion element 103R, it is difficult to convert all incident R light into p-polarized light. For this reason, s-polarized light is mixed in part of the R light emitted from the polarization conversion element 103R. The R light diffraction element 1420R, which is the first color light light branching portion, branches by diffracting polarized light having a specific vibration direction out of the R light emitted from the polarization conversion element 103R.

  FIG. 15 shows a schematic configuration of the R-light diffraction element 1420R. The R light diffraction element 1420R is configured by bonding glass GLA and an optically anisotropic substance M. A diffraction groove N is formed on the joint surface. The optically anisotropic material M is refracted by polarized light that vibrates in a direction along the longitudinal direction of the diffraction groove N (hereinafter referred to as “diffraction groove direction”) and polarized light that vibrates in a direction perpendicular to the diffraction groove direction. The rate is different. As the optically anisotropic substance M, for example, lithium niobate, liquid crystal, or the like can be used.

  The refractive index of the glass GLA of the diffraction element for R light 1420R is 1.5. For the optically anisotropic substance M, the refractive index for polarized light oscillating in the direction of the diffraction groove is 1.5, and the refractive index for polarized light oscillating in a direction perpendicular to the direction of the diffraction groove is 1.8. Here, the diffraction element for R light 1420R is arranged so that the direction of the diffraction groove and the vibration direction of the p-polarized light substantially coincide. In this case, there is no refractive index difference between the glass GLA and the optically anisotropic substance M for the p-polarized light. Therefore, the p-polarized light is transmitted through the diffraction groove N without being diffracted. On the other hand, polarized light that vibrates in a direction perpendicular to the diffraction groove direction, that is, s-polarized light, is diffracted by the diffraction groove N because the glass GLA and the optically anisotropic material M have different refractive indexes. Thereby, the R light diffraction element 1420R branches by diffracting the s-polarized light which is a part of the R light emitted from the polarization conversion element 103R.

  The R light diffraction element 1420R transmits p-polarized light of the incident R light in the direction of the R light spatial light modulator 110R (0th order light), and s-polarized light other than the R light spatial light modulator 110R. Diffraction in the direction of. The R light, which is p-polarized light that is transmitted in the direction of the spatial light modulator for R light 110R, is modulated according to the image signal by the spatial light modulator for R light 110R and converted into s-polarized light. The R light converted into s-polarized light by the R light spatial light modulator 110R enters the cross dichroic prism 112.

  The s-polarized light diffracted by the R light diffraction element 1420R in a direction other than the R light spatial light modulator 110R travels in the direction of the R light light detection unit 1402R. In this way, the R light diffraction element 1420R branches the light supplied from the first light source unit 701R into the direction of the R light spatial light modulator 110R and the direction of the light detection unit 1402R. The light detection unit 1402R detects the light branched by the R light diffraction element 1420R. The control unit 1405 controls the R light spatial light modulation device 110R so that the luminance distribution of the R light detected by the R light detection unit 1402R is substantially uniform.

  Next, the G light supplied from the second light source unit 701G will be described. The G light from the second light source unit 701G enters the polarization conversion element 103G. For example, the polarization conversion element 103G converts incident G light into substantially s-polarized light. The G light diffraction element 1420G is arranged so that the diffraction groove direction and the vibration direction of the s-polarized light substantially coincide. In this case, there is no refractive index difference between the glass GLA and the optically anisotropic substance M for the s-polarized light. Accordingly, the s-polarized light passes through the diffraction groove N without being diffracted. On the other hand, polarized light that vibrates in a direction perpendicular to the diffraction groove direction, that is, p-polarized light, is diffracted by the diffraction groove N because the glass GLA and the optically anisotropic material M have different refractive indexes. Accordingly, the G light diffraction element 1420G branches by diffracting the p-polarized light which is a part of the G light emitted from the polarization conversion element 103G.

  The G light traveling in the direction from the G light diffraction element 1420G to the G light spatial light modulator 110G is modulated in accordance with the image signal by the G light spatial light modulator 110G and converted to p-polarized light. The G light converted into p-polarized light by the G light spatial light modulator 110 </ b> G enters the cross dichroic prism 112. Further, the p-polarized light diffracted by the G light diffraction element 1420G is detected by the G light light detection unit 1402G, as in the description of the R light. The control unit 1405 controls the G light spatial light modulator 110G so that the luminance distribution of the G light detected by the light detection unit 1402G is substantially uniform.

  The B light supplied from the third light source unit 701B will be described. The B light from the third light source unit 701B is incident on the polarization conversion element 103B. For example, the polarization conversion element 103B converts incident B light into substantially p-polarized light. Similarly to the R light diffraction element 1420R, the B light diffraction element 1420B, which is the third color light beam splitting section, transmits p-polarized light and diffracts s-polarized light.

  The B light that has traveled straight from the B light diffractive element 1420B in the direction of the B light spatial light modulator 110B is modulated by the B light spatial light modulator 110B in accordance with the image signal and converted into s-polarized light. The B light converted into the s-polarized light by the B light spatial light modulator 110B enters the cross dichroic prism 112. The s-polarized light diffracted by the B-light diffraction element 1420B is detected by the B-light light detection unit 1402B, as in the description of the R light. The control unit 1405 controls the B light spatial light modulator 110B so that the luminance distribution of the B light detected by the light detection unit 1402B is substantially uniform.

  The diffractive elements 1420R, 1420G, and 1420B that are the light branching portions for the respective color lights are configured to guide the diffracted light to the respective light detection portions 1402R, 1402G, and 1402B, thereby detecting the luminance distribution of each color light by each light detection portion. can do. As a result, the brightness of each color light is kept constant, and the projector 1400 with less color unevenness can be obtained. Moreover, the light which is not converted into the specific polarization direction by each polarization conversion element is used for the detection by each light detection unit. Light that has not been converted into a specific polarization direction is not accurately modulated in the spatial light modulator, and this causes a reduction in the contrast of the projected image. For this reason, by arranging the diffraction elements 1420R, 1420G, and 1420B in the optical path, the light forming the projection image is not reduced. Thereby, there is an effect that uneven color can be reduced without impairing the brightness of the projected image of the screen 140. Alternatively, a light component that is not converted into a specific polarization direction may be positively generated, and the luminance of the light of this component may be detected.

  Note that the functions of the color light diffraction elements 1420R, 1420G, and 1420B may be configured to also function as the first polarizing plate (see FIG. 1). Since the first polarizing plate transmits polarized light having a specific vibration direction, each color light diffraction element 1420R, 1420G, 1420B of this embodiment can also function as the first polarizing plate. As a result, the number of components can be reduced, and color unevenness can be reduced with a simple configuration.

(Sixth embodiment)
FIG. 16 shows a schematic configuration of a projector according to the sixth embodiment of the invention. The same parts as those in the first embodiment and the third embodiment are denoted by the same reference numerals, and redundant description is omitted. The projector 1600 according to the present embodiment uses a tilt mirror device as a spatial light modulation device.

  The projector 1600 includes a first light source unit 1601R that supplies R light, a second light source unit 1601G that supplies G light, and a third light source unit 1601B that supplies B light. The first light source unit 1601R, the second light source unit 1601G, and the third light source unit 1601B have LEDs that are solid-state light emitting elements. Each light source unit is disposed in the vicinity of the incident side end surface of the projection lens 130.

  Light supplied from each light source unit enters a spatial light modulator 1610 that is a tilt mirror device. The spatial light modulator 1610 modulates incident light according to an image signal. One example of a tilt mirror device is the Texas Instruments Digital Micromirror Device (DMD). The light modulated by the spatial light modulator 1610 is emitted in the direction of the projection lens 130. The projection lens 130 projects the light emitted from the spatial light modulator 1610 onto the screen 140.

  The spatial light modulator 1610 has a plurality of movable mirror elements. The movable mirror element selectively moves between the first reflection position and the second reflection position in accordance with the image signal, and moves the incident light in the direction of the projection lens 130 (ON) or the direction other than the projection lens 130 (OFF ) To reflect. The movable mirror element 1610a reflects incident light in the direction of the projection lens 130 in the first reflection position. The movable mirror element 1610b reflects incident light in a direction other than the projection lens 130 in the second reflection position. The light L1 traveling in the direction of the projection lens 130 forms a projection image on the screen 140. The light L2 traveling in a direction other than the projection lens 130 enters the light detection unit 1602.

  For example, when detecting the luminance distribution of R light, only the first light source unit 1601R is turned on, and a period for driving the spatial light modulator 1610 is provided so that all the R light is incident on the light detection unit 1602. That is, during this period, all the movable mirror elements included in the spatial light modulator 1610 are in the second reflection position. And R light is detected during this period. Regarding the detection of the G light and the B light, similarly to the R light, only the color light to be detected is turned on, and all the movable mirror elements are set as the second reflection positions. Thereby, the light detection unit 1602 detects the respective luminance distributions of the R light, the G light, and the B light. Based on the luminance distributions of the R light, G light, and B light detected by the light detection unit 1602, the control unit 1605 makes the luminance distributions of the R light, G light, and B light substantially uniform. The spatial light modulator 1610 is controlled. Note that the control unit 1605 controls the time-division driving (subframe driving) of the movable mirror element included in the spatial light modulation device 1610 to make the luminance distribution of each color light substantially uniform.

  When the light detection unit 1602 detects light reflected from the spatial light modulation device 1610 in a direction other than the projection lens 130, the light detection unit 1602 can detect the luminance distribution of each color light. In addition, the light reflected in the direction of the light detection unit 1602 during image projection is a component of light that is unnecessary for forming a projected image. Accordingly, since the light forming the projection image is not reduced, a brighter projection image can be obtained than the configuration in which light is branched in the optical path of the projection light. Thus, there is an effect that a projector 1600 having a bright projection image with reduced color unevenness can be obtained.

  Next, lighting timings of the light source units 1601R, 1601G, and 1601B will be described. During one frame of the projected image, each color light LED is sequentially turned on to illuminate the spatial light modulator 1610. An observer integrates and recognizes R light, G light, and B light that are sequentially illuminated from each light source unit and modulated by the spatial light modulator 1610. For this reason, a full-color projection image is obtained on the screen 140. In order to sequentially project R light, G light, and B light and obtain a white projected image as a whole, the amount of luminous flux of G light requires 60 to 80% of the total luminous flux. If the output amount and quantity of the LEDs for each color light are the same, the amount of G light flux will be insufficient. Therefore, when the same number of LEDs for R light, G light, and B light are arranged, the lighting time of the G color LED is made longer than the lighting time of the R light LED and the B light LED. When the number of G light LEDs is larger than the number of R light LEDs and B light LEDs, the lighting time of the G light LEDs can be the same as or shorter than the lighting times of the other color light LEDs. is there. Thereby, a natural full-color image can be obtained.

(First Modification of Sixth Embodiment)
FIG. 17 shows a schematic configuration of a first modification of the sixth embodiment. The same parts as those of the projector 1600 are denoted by the same reference numerals, and redundant description is omitted. The projector 1700 is characterized in that the reflection mirror 1706 is disposed in the vicinity of the incident side end face of the projection lens 130 and the light detection unit 1702 is disposed in the vicinity of the spatial light modulator 1610.

  The light L2 traveling in a direction other than the projection lens 130 enters the reflection mirror 1706 disposed in the vicinity of the incident side end face of the projection lens 130. The reflection mirror 1706 reflects incident light in the direction of the light detection unit 1702. The light detection unit 1702 sequentially detects the luminance distribution of each of R light, G light, and B light from the reflected light from the reflection mirror 1706. In this modification, the light detection unit 1702 and the spatial light modulation device 1610 can be arranged on the same substrate PL. More preferably, the light detection unit 1702, the spatial light modulation device 1610, and the control unit 1605 can be configured integrally. As a result, the projector 1700 can have a simple configuration.

(Second Modification of Sixth Embodiment)
FIG. 18 shows a schematic configuration of a second modification of the sixth embodiment. The same parts as those of the projector 1600 are denoted by the same reference numerals, and redundant description is omitted. In the projector 1800, the first light source unit, the third light source unit, and the second light source unit are arranged at substantially symmetric positions with respect to the optical axis AX of the projection lens 140.

  The projector 1800 includes a first light source unit 1801R that supplies R light, a second light source unit 1801G that supplies G light, and a third light source unit 1801B that supplies B light. The 1st light source part 1801R, the 2nd light source part 1802G, and the 3rd light source part 1801B have LED which is a solid light emitting element. Light supplied from each light source unit enters a spatial light modulator 1810 that is a tilt mirror device. The spatial light modulator 1810 modulates incident light according to an image signal. The light modulated by the spatial light modulator 1810 is emitted toward the projection lens 130. The projection lens 130 projects the light emitted from the spatial light modulator 1810 onto the screen 140.

  Spatial light modulator 1810 has a plurality of movable mirror elements. The movable mirror element selectively moves between the first reflection position and the second reflection position in accordance with the image signal, and moves the incident light in the direction of the projection lens 130 (ON) or the direction other than the projection lens 130 (OFF ) To reflect.

  As shown in FIG. 18, the movable mirror element 1810a in the first reflection position reflects incident light from the first light source unit 1801R and the third light source unit 1801B in the direction of the projection lens 130 (light L1). In addition, the movable mirror element 1810a at the first reflection position reflects incident light from the second light source unit 1801G in a direction other than the projection lens 130 (light L4). Furthermore, the movable mirror element 1810b at the second reflection position reflects incident light from the second light source unit 1801G in the direction of the projection lens 130 (light L3). In addition, the movable mirror element 1810b at the second reflection position reflects incident light from the first light source unit 1801R and the third light source unit 1801B in the direction of the projection lens 130 (light L2). The light L1 and the light L3 traveling in the direction of the projection lens 130 form a projected image on the screen 140.

  Light L2 traveling in a direction other than the projection lens 130 from the first light source unit 1801R and the third light source unit 1801B enters the light detection unit 1802RB. The light detection unit 1802RB detects the luminance distribution of each of the R light and the B light. Further, the light L4 traveling in a direction other than the projection lens 130 from the second light source unit 1801G enters the light detection unit 1802G. The light detection unit 1802G detects the luminance distribution of the G light.

  For example, when detecting the luminance distribution of the R light, only the first light source unit 1801R is lit and a period for driving the spatial light modulator 1810 is provided so that all the R light is incident on the light detection unit 1802RB. That is, during this period, all the movable mirror elements included in the spatial light modulator 1810 are in the second reflection position. And R light is detected during this period. Regarding the detection of the B light, similarly to the R light, only the third light source unit 1801B is turned on, and all the movable mirror elements are set as the second reflection positions. Thereby, the light detection unit 1802RB detects the luminance distribution of each of the R light and the B light. When detecting the luminance distribution of G light, only the second light source unit 1801G is turned on, and a period for driving the spatial light modulator 1810 is provided so that all the G light is incident on the light detection unit 1802G. That is, during this period, all movable mirror elements included in the spatial light modulator 1810 are in the first reflection position. And G light is detected during this period. Thereby, the light detection unit 1802G detects the luminance distribution of the G light. As described above, the reflection position of the movable mirror element is inverted between the detection of the R light and the B light and the detection of the G light.

  Based on the respective luminance distributions of the R light and B light detected by the light detection unit 1802RB, and the G light detected by the light detection unit 1802G, the control unit 1805 can detect each of the R light, G light, and B light. The spatial light modulator 1810 is controlled so that the luminance distribution of the light becomes substantially uniform. Note that the spatial light modulation device 1810 of the projector 1800 according to this modification makes the luminance distribution of each color light substantially uniform by controlling time-division driving (sub-frame driving) of the movable mirror element.

  The light detection unit 1802RB detects the R light and B light reflected from the spatial light modulation device 1810 in the direction other than the projection lens 130, so that the light detection unit 1802RB detects the luminance distribution of the R light and the B light. Can do. The light detection unit 1802G detects the G light reflected in the direction other than the projection lens 130 from the spatial light modulator 1810, whereby the light detection unit 1802G can detect the luminance distribution of the G light. Further, the light reflected in the direction of the light detection units 1802RB and 1802G during image projection is a component of light that is unnecessary for forming a projected image. Accordingly, since the light forming the projection image is not reduced, a brighter projection image can be obtained than the configuration in which light is branched in the optical path of the projection light. As a result, there is an effect that a projector 1800 having a bright projection image with reduced color unevenness can be obtained.

  In the projector 1800 of this modification, the first light source unit 1801R, the third light source unit 1801B, and the second light source unit 1801G are arranged at positions that are substantially symmetrical with respect to the optical axis AX of the projection lens 130. Thereby, the freedom degree of arrangement | positioning of LED for each color light can be made high. For example, the number of G light LEDs of the second light source unit 1801G may be larger than the number of R light LEDs of the first light source unit 1801R and the number of B light LEDs of the third light source unit 1801B. As a result, it is possible to obtain a projected image with good color balance with a simple configuration. At this time, the drive polarity of the movable mirror element is reversed between the lighting time of the G light LED and the lighting time of the R light and B light LEDs. As a result, the spatial light modulator 1810 performs light modulation in accordance with ON / OFF of the image signal, and can obtain a full-color projection image.

(Seventh embodiment)
FIG. 19 shows a schematic configuration of a printer 1900 according to the seventh embodiment of the present invention. The illumination device 1901 of the printer 1900 includes a first light source unit that supplies R light, a second light source unit that supplies G light, and a third light source unit that supplies B light. A 1st light source part, a 2nd light source part, and a 3rd light source part have LED which is a solid light emitting element. In addition, the printer 1900 includes a temperature detection unit, a storage unit, and a control unit (all not shown), like the projector 100 according to the first embodiment.

  Light supplied from the illumination device 1901 enters the spatial light modulator 1910. A DMD can be used as the spatial light modulator 1910. The light reflected by the spatial light modulator 1910 forms an image on the photographic paper piece P by the imaging lens 1930. A reflection mirror 1903 for bending the optical path is provided between the imaging lens 1930 and the photographic paper piece P.

  The spatial light modulator 1910, which is a DMD, is an element in which, for example, 16 μm square movable mirror elements are two-dimensionally arranged in a substrate shape at 1 μm intervals. By controlling the rotation of each movable mirror element, on / off of the region corresponding to each movable mirror element is controlled. In the case of this embodiment, the movable mirror element of the spatial light modulator 1910 is controlled so that the light supplied from the illumination device 1901 is reflected in the direction of the imaging lens 1930. Thereby, a minute area on the photographic paper piece P corresponding to the movable mirror element is exposed.

  On the other hand, the movable mirror element of the spatial light modulator 1910 is controlled so that the light supplied from the illumination device 1901 is reflected in a direction other than the imaging lens 1930. At this time, a minute region on the photographic paper piece P corresponding to the movable mirror element is not exposed. By performing such control for each movable mirror element, an image of dots is exposed to a predetermined area 1904 on the photographic paper piece P (latent image is formed).

  In the spatial light modulator 1910, movable mirror elements are two-dimensionally arranged so that a plurality of scanning lines in a direction orthogonal to the conveyance direction of the photographic paper piece P can be exposed simultaneously. For example, a mirror for 192 scanning lines It is configured as an array. In addition, a color filter (not shown) included in the lighting device 1901 has a disk shape divided into R, G, and B color filters every 120 degrees, for example, and is rotated at a constant speed. Therefore, R, G, and B light sequentially enter the spatial light modulator 1910 at regular intervals. The photographic paper pieces P are continuously conveyed in the arrow S direction. The spatial light modulator 1910 reflects and exposes the R light, G light, and B light that are illuminated in time series so as to form a color image on the photographic paper piece P. Thereby, a full color image can be obtained on the photographic paper piece P. Details of the operation of a printer of a type that exposes photographic paper are described in, for example, Japanese Patent Application Laid-Open No. 2001-133295.

  Based on the relationship between the temperature of each light source unit and the luminance distribution of each color light, the control unit of the printer 1900 according to this embodiment performs spatial light modulation so that the luminance distribution of each color light is substantially the same in the predetermined region 1904. The device 1910 is controlled. As a result, the brightness of each color light is kept constant, and the printer 1900 with less color unevenness in the displayed image can be obtained. Further, similarly to the projector according to the above-described embodiment, the light detection unit may detect the luminance distribution of each color light and control the spatial light modulation device 1910. As a result, the brightness of each color light is kept constant, and the printer 1900 with less color unevenness in the displayed image can be obtained.

  Note that although an example of an optical apparatus according to the present invention has been described using a printer that exposes photographic paper, the present invention is not limited to a printer. The present invention can be easily applied to any optical apparatus that requires illumination light having a bright and uniform illuminance distribution. For example, the present invention can be effectively applied to a semiconductor exposure apparatus or the like. In each of the embodiments described above, the LED is used as the solid light emitting element included in each light source unit. However, a semiconductor laser or electroluminescent (EL) may be used as the solid light emitting element in the light source unit. Furthermore, the present invention is not limited to the case where a solid light emitting element is used for the light source unit, and can be appropriately applied if a plurality of light source units having different wavelength regions are used.

  100, 300, 700, 1200, 1300, 1400, 1600, 1700, 1800 ... projector, 101R, 301R, 701R, 1601R, 1801R ... first light source unit, 101G, 301G, 701G, 1601G, 1801G ... second light source unit, 101B, 301B, 701B, 1601B, 1801B ... third light source unit, 102R, 102G, 102B ... temperature detection unit, 103R, 103G, 103B ... polarization conversion element, 105, 305, 705, 1205, 1305, 1405, 1605, 1805 Control unit 107, 307, 707 Storage unit 110R Spatial light modulator for R light 110G Spatial light modulator for G light 110B Spatial light modulator for B light 112 Cross dichroic prism 115R , 115G, 115B ... Liquid crystal panel 116R, 116G, 116B ... first polarizing plate, 117R, 117G, 117B ... second polarizing plate, 130 ... projection lens, 140 ... screen, 304R, 304G, 304B, 704R, 704G, 704B ... light source drive circuit, 702, 1402R, 1402G, 1402B, 1602, 1702, 1802RB, 1802G... Light detection unit, 702a, 702b ... sensor, 708 ... detection optical system, H ... interpolation value, 1220 ... beam splitter, 1220a ... beam splitting surface, 1320, 1420R, 1420G, 1420B ... Diffraction element, GLA ... Glass, M ... Optically anisotropic material, N ... Diffraction groove, 1610, 1810, 1910 ... Spatial light modulator, 1610a, 1610b, 1810a, 1810b ... Movable mirror element, 1706 , 1903 ... Reflecting mirror, P ... substrate, 1900 ... printer, 1901 ... lighting device 1930 ... imaging mirror.

Claims (9)

A first light source for supplying first color light;
A second light source for supplying second color light;
A third light source for supplying third color light;
A first temperature detection unit disposed in the vicinity of the first light source unit for detecting the temperature of the first light source unit;
A second temperature detection unit disposed in the vicinity of the second light source unit and detecting a temperature of the second light source unit;
A third temperature detection unit disposed in the vicinity of the third light source unit for detecting the temperature of the third light source unit;
A spatial light modulator that modulates light from the first light source unit, the second light source unit, and the third light source unit according to an image signal;
A projection lens that projects light modulated by the spatial light modulator onto a screen;
The temperature change amount of the first light source unit, the shift amount of the wavelength region of the first color light from the first light source unit, the first color light for adjusting white balance, the second color light, and the first The relationship with the light amount shift amount of three-color light,
The temperature change amount of the second light source unit, the shift amount of the wavelength region of the second color light from the second light source unit, the first color light for adjusting white balance, the second color light, and the first The relationship with the light amount shift amount of three-color light,
The temperature change amount of the third light source unit, the shift amount of the wavelength region of the third color light from the third light source unit, the first color light for adjusting white balance, the second color light, and the first A storage unit for storing the relationship between the light amount shift amount of the three color lights;
First temperature detecting unit before reporting, the temperature change of the second temperature detection unit, and the third the first light source part respectively detected by the temperature detector, the second light source unit, and the third light source unit The first light source unit, the first light source unit, and the second light source unit for adjusting white balance based on a relationship between light amount shift amounts of the first color light, the second color light, and the third color light stored in the storage unit. A control unit for controlling the light amount of the two light source units and the third light source unit;
A projector comprising: The storage unit further includes a relationship between a temperature of the first light source unit and a luminance distribution of the first color light from the first light source unit, a temperature of the second light source unit, and the second light source unit. Storing the relationship between the luminance distribution of the second color light and the relationship between the temperature of the third light source unit and the luminance distribution of the third color light from the third light source unit;
The control unit further includes the first light source unit, the second light source unit, and the third light source respectively detected by the first temperature detection unit, the second temperature detection unit, and the third temperature detection unit. The first color light and the second color light in the screen based on the relationship between the temperature of the part and the luminance distribution of the first color light, the second color light, and the third color light stored in the storage unit 2. The projector according to claim 1, wherein the spatial light modulation device is controlled so that luminance distributions of the third color light and the third color light are substantially uniform. The storage unit further stores a gradation correction value for correcting the gradation of the projected image,
The control unit includes: the first light source unit, the second light source unit, and the third light source unit detected by the first temperature detection unit, the second temperature detection unit, and the third temperature detection unit, respectively. By changing and using the gradation correction value based on the temperature, the luminance distribution of each of the first color light, the second color light, and the third color light is substantially uniform on the screen. The projector according to claim 2, wherein the projector controls a spatial light modulator. A light detection unit for detecting a luminance distribution of each of the first color light, the second color light, and the third color light;
The control unit is configured to determine the first color light, the second color light, and the first color light based on respective luminance distributions of the first color light, the second color light, and the third color light detected by the light detection unit. The projector according to any one of claims 1 to 3, wherein the spatial light modulator is controlled so that the luminance distributions of the three color lights are substantially uniform.   5. The detection optical system according to claim 4, further comprising a detection optical system that guides the first color light, the second color light, and the third color light projected from the projection lens onto the screen, respectively, to the light detection unit. Projector. The first color light, the second color light, and the third color light, which are provided in an optical path between the spatial light modulation device and the projection lens and are modulated by the spatial light modulation device, are respectively directed to a projection lens direction and the projection lens. It further has a light branching part that branches in the direction of the light detection part,
The projector according to claim 4, wherein the light detection unit detects light branched by the light branching unit. The light detection unit is a first color light detection unit that detects the first color light, a second color light detection unit that detects the second color light, and a third color light light that detects the third color light. Consisting of a detector,
Provided in an optical path between the first light source unit and the spatial light modulation device, the first color light from the first light source unit is converted into the direction of the spatial light modulation device and the light detection unit for the first color light. A first color light branching unit that branches into a direction;
Provided in the optical path between the second light source unit and the spatial light modulator, the second color light from the second light source unit is transmitted to the direction of the spatial light modulator and the second color light detection unit. A second color light branching portion that branches into a direction;
Provided in an optical path between the third light source unit and the spatial light modulator, and the third color light from the third light source unit is transmitted to the direction of the spatial light modulator and the light detector for the third color light. A third color light branching unit that branches into a direction;
The projector according to claim 4, further comprising: Further, the spatial light modulator is configured to receive each of the first color light from the first light source unit, the second color light from the second light source unit, and the third color light from the third light source unit. A tilt mirror device comprising a movable mirror element that reflects in the direction of the projection lens or in a direction other than the projection lens,
The projector according to claim 4, wherein the light detection unit detects light reflected in a direction other than the projection lens by the spatial light modulation device. A first light source for supplying first color light;
A second light source for supplying second color light;
A third light source for supplying third color light;
A spatial light modulator that modulates light from the first light source unit, the second light source unit, and the third light source unit according to an image signal;
An imaging lens for imaging light modulated by the spatial light modulator on a predetermined surface;
A light detection unit for detecting respective luminance distributions of the first color light, the second color light, and the third color light;
Based on the respective luminance distributions of the first color light, the second color light, and the third color light detected by the light detection unit, the first color light, the second color light, and the third color on the predetermined surface . A control unit for controlling the spatial light modulation device so that the respective luminance distributions of the colored lights are substantially uniform;
A first temperature detection unit disposed in the vicinity of the first light source unit for detecting the temperature of the first light source unit;
A second temperature detection unit disposed in the vicinity of the second light source unit and detecting a temperature of the second light source unit;
A third temperature detection unit disposed in the vicinity of the third light source unit for detecting the temperature of the third light source unit;
The relationship between the temperature of the first light source unit and the luminance distribution of the first color light from the first light source unit, the temperature of the second light source unit and the luminance distribution of the second color light from the second light source unit And a storage unit that stores the relationship between the temperature of the third light source unit and the luminance distribution of the third color light from the third light source unit,
The control unit further includes the first light source unit, the second light source unit, and the third light source respectively detected by the first temperature detection unit, the second temperature detection unit, and the third temperature detection unit. Based on the relationship between the temperature of the unit and the luminance distribution of the first color light, the second color light, and the third color light stored in the storage unit, the first color light and the second color on the predetermined surface An optical apparatus, wherein the spatial light modulator is controlled so that the luminance distributions of the color light and the third color light are substantially uniform.

Images