JP2009198570A - Image display apparatus and projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image display apparatus that can display a higher contrast, high quality color image by further reducing unnecessary light. <P>SOLUTION: The image display apparatus includes: an illuminating means for emitting light rays of respective colors; and an image display means for modulating light emitted by the illuminating means, wherein the illuminating means has a light-source light quantity control means in which optical control elements that emit light while controlling a quantity of light through a time division control are arranged in a matrix in one plane, the image display means has a plurality of pixels arranged in a matrix in one plane and used for modulating a quantity of light emitted by the illuminating means in synchronization with the time division control of the optical control elements, and the light-source light quantity control means and image display means have such a predetermined relation that light emitted from the optical control elements illuminates specific pixels. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image display device and a projection device.

  In recent years, a projection apparatus that projects illumination light modulated by an image display element such as a liquid crystal panel (LCD) or a DMD (Digital Micromirror Device) of Texas Instruments, Inc. on a projection surface such as a screen is used as a projector for a home theater. It has come to be widely used.

  Such a projection apparatus normally projects an image display element that modulates illumination light, an illumination optical system for irradiating the image display element with illumination light, and the modulated light from the image display element onto a projection surface. A projection optical system.

  The quality required for an image projected and displayed on a screen or the like, which is a projection surface, by the projection device is desired to be higher as the display image becomes higher in definition. One of the quality improvements to cope with the higher quality of the display image is higher contrast. For example, there is a method of arranging two liquid crystal elements shown below in series.

  In Patent Document 1, two liquid crystal elements are arranged in series, and the amount of light reaching the screen out of the amount of light incident on the liquid crystal element is the product of the transmittance of the two liquid crystal elements. In this way, when a black level driving signal having a signal level of 0 (zero) is input to each of the two liquid crystal elements, the light transmittance is A after passing through one liquid crystal panel having A as the transmittance. The light transmittance is the square of A, and the transmittance can be kept lower and closer to the black level, and the contrast range can be expanded.

In Patent Document 2, a first liquid crystal element for illumination control and a second liquid crystal element for image display are provided, and the area and light quantity in which the second liquid crystal element is illuminated by light from the light source The liquid crystal element is controlling. By illuminating a specific area of the second liquid crystal element for image display with a necessary light quantity corresponding to a necessary display luminance by controlling the first liquid crystal element, the second light illuminated with an excessive light quantity is necessary. Contrast is enhanced by suppressing unnecessary light such as stray light generated from the liquid crystal element.
US Pat. No. 5,978,142 Japanese Patent Laid-Open No. 2001-1000068

  Of course, a color image is included in a display image for which high quality is desired by a projector using a liquid crystal element (liquid crystal panel), DMD, or the like. A case where a color image is displayed by a liquid crystal projector having a configuration in which two liquid crystal elements described in Patent Document 2 are arranged in series will be described with reference to FIGS. FIG. 10 shows a configuration of a liquid crystal projector as a conventional example. FIG. 11 schematically shows a state in which the amount of light emitted from the discharge lamp 1 changes before being emitted from the projection lens 10.

  The light generated from the discharge lamp 1 is cut by the UV / IR cut filter 3 except for the visible light region. Thereafter, the polarization direction is made almost uniform by the PS conversion optical element 11, and the light is divided by the first fly-eye integrator 12 to form an image on each cell of the first liquid crystal element 7 '. At this stage, light (FIG. 11 (a)) emitted from the discharge lamp 1 and having the amount of white (W) light reaching the first liquid crystal element 7 'as 300 (the amount of light for illustration) is shown. The first liquid crystal element 7 ′ attenuates to half of 150 (FIG. 11B). Note that a reduction in the amount of light due to loss due to uncontrolled transmittance or reflectance in an optical element or the like will be omitted for ease of explanation.

  After the attenuated light passes through the second fly's eye integrator 13 and the relay lens 14a, the dichroic mirrors 15a and 15b divide the white light of the discharge lamp 1 into three colors. Assuming that white light is equally divided into three colors of R (red), G (green), and B (blue), each light quantity is divided into 50 (FIG. 11 (c)). Thereafter, the light of each color passes through the relay lenses 14b and 14c, the field lenses 17a, 17b and 17c, the polarizing plates 18a to 18f, and the like, and then enters the second liquid crystal elements 9′a, 9′b and 9′c of the respective colors. To reach.

  Assuming that the light amounts of R, G, and B constituting the image displayed on the screen (not shown) by the projection lens 10 are 10, 20, and 50, the light amounts of the respective colors constituting the image from the light amounts 50 of the respective color components. Adjustment is performed by the transmittance control of the second liquid crystal elements 9′a, 9′b, 9′c (FIG. 11D). Finally, the respective color lights are combined by the cross prism 19 and emitted from the projection lens 10 toward the screen (FIG. 11E).

  In this case, the amount of light attenuated by the first liquid crystal element 7 ′ shown in FIG. 11B is 150, which is the amount of light necessary to irradiate the liquid crystal element 9′c corresponding to B (blue). This is to ensure For this reason, the illumination light quantity of 2nd liquid crystal element 9'a, 9'b corresponding to R (red) and G (green) becomes larger than necessary in order to ensure the light quantity required for B (blue). End up. For this reason, the light reflected or scattered by the incident surface of the second liquid crystal element becomes unnecessary light such as stray light and enters the projection lens 10 and reaches the screen to reduce the contrast of the display image, thereby reducing the image quality. The problem of being invited arises. Regarding the contrast in such color image display, neither of Patent Documents 1 and 2 is mentioned.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide an image display device that enables high-quality color image display with higher contrast by further reducing unnecessary light. An object of the present invention is to provide a projection apparatus provided with this image display apparatus.

  Said subject is solved by the following structures.

1. Illumination means for emitting light of multiple colors;
In an image display device comprising image display means for modulating light emitted from the illumination means,
The illumination means includes a light source light quantity control means in which a plurality of light control elements that emit light by controlling the light quantity by time division control are arranged in a matrix in one plane,
The image display means includes a plurality of pixels arranged in a matrix within one plane, and a pixel that modulates the amount of light emitted from the illumination means in synchronization with time-division control of the light control element,
The image display device, wherein the light source light quantity control means and the image display means have a predetermined relationship in which light emitted from a specific light control element illuminates a specific pixel.

2. The illumination means includes a discharge lamp,
A color wheel that receives light from the discharge lamp and sequentially decomposes and outputs the light into a plurality of colors; and
The light source light quantity control means includes a matrix of light reflection angle variable mirror elements that time-division-control light emitted from the color wheel by selectively determining a reflection direction according to an input illumination signal. 2. The image display device according to 1, wherein the image display devices are mirror devices arranged in a shape.

  3. 2. The image display device according to 1, wherein the light control element is a light emitting diode or a laser diode.

  4). In the image display means, a light reflection angle variable mirror element that controls time-division of light emitted from the illumination means by selectively determining a reflection direction according to an input video signal is formed in a matrix in a plane. 4. The image display device according to any one of claims 1 to 3, wherein the image display device is a mirror device arranged in an array.

5. The number of the light control elements in the light source light amount control means is equal to the number of the pixels in the image display means,
Any one of 1 to 4, wherein the predetermined relationship is a relationship in which light emitted from one light control element illuminates one pixel corresponding to the light control element on a one-to-one basis. The image display device according to one item.

6). The number of the light control elements in the light source light quantity control means is less than the number of the pixels in the image display means,
The predetermined relationship is a relationship in which light emitted from one light control element illuminates a plurality of the pixels corresponding to the light control element. The image display device described in 1.

  7. The predetermined relationship is a relationship in which light emitted from a plurality of the light control elements illuminates one or more pixels corresponding to the light control elements. The image display device according to claim 1.

  8). The image display apparatus according to any one of claims 1 to 7, wherein the light source quantity control means and the image display means have a substantially conjugate relationship.

  9. The light amount emitted from the light control element in the light source light amount control means is a light amount corresponding to a pixel having the highest luminance value among pixels corresponding to the light control element. Image display device.

10. The image display device according to any one of 1 to 9,
A projection apparatus comprising: a projection optical system that projects modulated light from the image display apparatus onto a projection surface.

  According to the image display device of the present invention and the projection device including the image display device, unnecessary light can be further reduced, and high-quality color image display with higher contrast can be realized.

Although the present invention will be described based on the illustrated embodiment, the present invention is not limited to the embodiment. Hereinafter, a projection apparatus and the like provided with an image display apparatus according to the present invention will be described with reference to the drawings. In addition, the same code | symbol and each corresponding part of each embodiment are attached | subjected the same code | symbol, and duplication description is abbreviate | omitted suitably.
(First embodiment)
FIG. 1 shows a projection apparatus 500 as an example of the projection apparatus according to the present invention, and the projection apparatus will be described using this. The projection apparatus 500 includes an image display apparatus including a discharge lamp 1 to a second mirror device (hereinafter referred to as MD) 9 and a projection lens 10 that is a projection optical system.

  Light that is emitted from the discharge lamp 1 having a reflector with a parabolic surface as a reflecting surface and that serves as illumination light passes through the condensing optical system 2, and components other than visible light are cut by the UV / IR cut filter 3. After that, the light enters the color wheel 4. The reflecting surface of the reflector provided in the discharge lamp 1 may be an ellipsoidal surface, the discharge lamp 1 may be disposed at the focal position, and the light beam emitted from the discharge lamp 1 may be incident on the color wheel 4 as convergent light.

  The color wheel 4 includes three color filters that respectively transmit light of wavelengths R (red), G (green), and B (blue), and each color filter has a fan shape obtained by dividing a disc into three equal parts. These three color filters are fixed to the frame to form a disk shape. By inserting and rotating the color wheel 4 perpendicular to the optical path, the white light incident on the color wheel 4 is equally divided into three colors that are sequentially switched in time. Note that the color filter is not limited to a combination of three colors R, G, and B. For example, a combination of three colors C (cyan), M (magenta), and Y (yellow) can be used. Other combinations that can be displayed may be used. Moreover, it is not limited to three colors, and a combination of four colors and four divisions such as R, G, B, and Y may be used. In order to prevent color flickering, combinations of three colors and six divisions such as R, G, B, R, G, and B, or more divisions may be used. Further, the division ratio of the three colors may be appropriately changed according to the light source light amount.

  The light beam that has passed through the color wheel 4 enters the rod integrator 5. The light beam incident on the rod integrator 5 is mixed by being repeatedly reflected on the wall surface, and the uniformity of the in-plane light quantity distribution is enhanced on the exit surface of the rod integrator 5. The light emitted from the rod integrator 5 illuminates the first mirror device (hereinafter referred to as MD) 7 serving as the light source light quantity control means by the illumination relay optical system 6 with a uniform light quantity distribution. The discharge lamp 1 to the first MD 7 described so far constitute the illumination means according to the present invention.

  Here, the first MD 7 and the second MD 9 which will be described later will be described. The first MD 7 and the second MD 9 are mirror devices each having a plurality of minute light reflection angle variable mirror elements of about 10 μm square arranged in a matrix in one plane. The mirror element included in the first MD 7 is a light control element according to the present invention, and the mirror element included in the second MD 9 is a pixel according to the present invention. Each of these mirror elements included in the mirror device selectively reflects light incident on the mirror in one of two different directions according to an input signal. An example of such a mirror device is DMD (Digital Micromirror Device). DMD is suitable for light time-division control (switching control of ON / OFF state described later) because the response speed of the mirror element is fast, and is preferable because light utilization efficiency is high because reflection is used. Hereinafter, both the first MD7 and the second MD9 will be described as DMDs.

  When the reflection angle of the mirror element included in the DMD is set to a desired direction (ON state), a signal input to the DMD is referred to as an ON signal, and a signal input when the DMD is not set to the desired direction (OFF state) is an OFF signal. I will call it. In addition, the light incident on the mirror element in the ON state is deflected and emitted, and the light emitted from the deflected light incident on the mirror element in the OFF state is referred to as OFF light. .

  The RGB light emitted from the relay optical system 6 sequentially illuminates the first MD 7 with each RGB color, and the light illuminating the first MD 7 is modulated by a light control element provided in the first MD 7. The light is reflected and enters the relay optical system 8. Since the light emitted from the relay optical system 8 illuminates the second MD 9, the second MD 9 is sequentially illuminated with RGB colors. Since the first MD7 and the second MD9 are in a conjugate relationship by the relay optical system 8, the light reflected from the first MD7 in the ON state can efficiently illuminate the second MD9.

  The number of mirror elements that are light control elements of the first MD7 according to the present invention is equal to the number of mirror elements that are pixels of the second MD9, and the first MD7 and the second MD9 are one The light reflected from the light control element illuminates one pixel corresponding to the light control element on a one-to-one basis. For example, the light control element 7c of the first MD 7 schematically shown in FIG. 3 corresponds to the pixel 9c of the second MD 9 on a one-to-one basis. Of the light illuminating the light control element surface of the first MD7, the reflected light from the light control element 7c in the ON state travels toward the second MD9 as ON light, and corresponds to the light control element 7c on a one-to-one basis. The second MD9 pixel 9c is configured to illuminate.

  The light of each color of RGB divided by the color wheel 4 at the same time sequentially illuminates the light control element 7c, and the light of each color reflected as ON light by the light control element 7c illuminates the pixel 9c by the relay optical system 8. . At this time, similarly to the light control element 7c and the pixel 9c, the other light control elements constituting the first MD 7 also illuminate the pixels of the second MD 9 corresponding one-to-one.

  As shown in FIG. 1, a first MD control device 24 is connected to the first MD 7, and a second MD control device 25 is connected to the second MD 9. The first MD control device 24 outputs an illumination signal for controlling the ON / OFF state to each of the plurality of light control elements included in the first MD 7 to the first MD 7, and the second MD control device. 25 outputs a video signal for controlling the ON / OFF state of each of the plurality of pixels provided in the second MD 9 to the second MD 9.

  The first MD control device 24 and the second MD control device 25 are based on the same image data supplied from the image data supply unit 23 and are synchronously connected to the first MD 7 and the second MD 7 respectively. The light control element and the pixel included in the pMD 9 are controlled.

  The light that illuminates the second MD 9 is modulated and reflected by the pixels included in the second MD 9, enters the projection lens 10, and forms an image on the screen. The pixels of the second MD9 form images corresponding to the respective colors in synchronization with the color of the light that illuminates the second MD9, and project this image onto the screen by the projection lens 10, thereby causing an afterimage of the eye. A color image is displayed using the phenomenon. In the first MD 7 and the second MD 9, the light emitted from the discharge lamp 1 is inputted with both the first MD 7 and the second MD 9, and the ON light from both is projected into the projection optical system. The projection lens 10 is configured to display an image on the screen.

  Here, a description will be given with reference to FIG. 2 until the white light emitted from the discharge lamp 1 is controlled and projected onto a screen (not shown) to form an image. In FIG. 2, I represents light intensity, t represents time, and T represents a frame rate.

  FIG. 2A schematically shows that the white light W emitted from the discharge lamp 1 has a constant luminance without depending on time. The white light W in this state enters the color wheel 4. FIG. 2B shows the state of light when emitted from the color wheel 4. The color wheel 4 divides the white light W from the discharge lamp 1 at the same time by rotating once in 1 / T time. For convenience of explanation here, the intensity I of the time-division-divided light is normalized to 1 for each color constituting white, and the time width 1 / (3 × T) in which each color is equally-divided is 100. handle. The amount of light of each color divided at the same time by the color wheel 4 is 100 (luminance × time width) for all of R (red), G (green), and B (blue). It should be noted that a change in the amount of light caused by a loss caused by transmittance or reflectance of an optical element or the like other than the light amount control by the first MD 7 and the second MD 9 described below will be omitted for ease of explanation.

  As shown in FIG. 2B, the light that has been time-divided by the color wheel 4 is guided to the first MD 7 by the relay optical system 6 and illuminates the light control element provided in the first MD 7. Here, the second MD control device 25 controls one pixel of the second MD9 based on the image data supplied from the image data supply unit 23, and pays attention to one pixel 9c. As shown in FIG. 2C, for example, the image formed by the pixel 9c has an R time width of 10 and a G time width of 10 G starting from the start time of each color obtained by dividing the frame period 1 / T into three. It is assumed that the time width of 20 and B is 50.

  In this case, the first MD control device 24 that controls the first MD 7 is supplied with the same image data as the second MD control device 25, and the light control element is turned on in synchronization with the pixel ON / OFF control. / OFF control (time division control) is performed. For this reason, the light control element 7c of the first MD 7 corresponding one-to-one with the pixel 9c also has the same start time and the same time width (the time width of R is 10, as shown in FIG. 2D). The time width of G is 20 and the time width of B is 50).

  As described above, the control method of the first MD7 and the control method of the second MD9 can be made the same, so that the control configuration of the image display apparatus can be simplified. Further, this control method can be the same as the control method of one image display DMD in a conventional DMD single-plate type projector that sequentially illuminates with time-divided RGB colors. Therefore, in the conventional projection apparatus, unnecessary light can be further reduced by replacing the illumination system with, for example, an illumination system including the discharge lamp 1 to the relay optical system 8 shown in FIG. It can be set as the projection apparatus which enables a higher quality image display.

  As shown in the projection apparatus 510 of FIG. 4, the light emitted from the plurality of light control elements of the first MD7 irradiates one pixel of the second MD9, whereby the first MD7 shown in FIG. The same effect as in the case where the light control element and the second MD9 pixel correspond one-to-one can be obtained.

  The case in which the light control elements of the first MD7 and the second MD9 and the pixels correspond one-on-one is most effective in improving the contrast because unnecessary light can be removed most efficiently, but the first MD7 and the second MD9. There is a case where the degree of difficulty in positioning for making each of these elements correspond one-to-one is high, which may cause an increase in cost. In such a case, the light emitted from the plurality of light control elements of the first MD7 irradiates one or more pixels of the second MD9 as in the projection apparatus 510 of FIG. Unnecessary light can be reduced as compared with a conventional DMD single-plate type projector. Thereby, adjustment at the time of assembly can be made unnecessary or simplified.

  The projector 510 will be described in detail with reference to FIG. In the projection device 510, a discharge lamp and a projection lens are omitted. FIG. 4A is a diagram showing a schematic configuration of the projection apparatus 510. FIG. 4B shows two specific pixels C and D in the second MD9. The numerical values in the squares of the pixels C and D indicate the time width of the ON light. FIG. 4C shows two light control element groups A and B composed of a plurality (9 in the figure) of light control elements respectively corresponding to the two specific pixels C and D shown in FIG. 4B. Is shown. The numerical values in the squares of the light control element groups A and B indicate the time width of the ON light.

  Examples of specific control methods for the first MD 7 and the second MD 9 are shown below. When the time width of, for example, R (red) ON light emitted from the pixel C on the second MD 9 as the image display means is 25 as shown in FIG. 4B, the light source light amount corresponding to the pixel C As shown in FIG. 4C, the time width of R (red) ON light emitted from the nine light control elements constituting the light control element group A on the first MD 7 as the control means is all 25. To.

  Furthermore, when the time width of the R (red) ON light emitted from the pixel D near the pixel C on the second MD 9 is set to 20 as shown in FIG. Of the light control element group B consisting of nine light control elements on one MD7, the time width of the ON light in the part S overlapping the range of the light control element group A is 25, and the light control element group excluding the part S The time width of R (red) ON light emitted from B is assumed to be 20. That is, the light control element emits an illumination light amount corresponding to the pixel having the highest luminance value among the corresponding pixels.

  The increase in the amount of light that illuminates the pixel D by the portion S can be easily adjusted by the time width of the ON light of the pixel D. In this way, the amount of light for illuminating the pixels can be suppressed as much as possible so as not to be excessively supplied.

  The projection device 510 is provided with a calculation unit 26. Based on the image data from the image data supply unit 23, the calculation unit 26 calculates the ON light time width reflecting the overlapping state of the first MD7 light control element groups corresponding to the respective pixels of the second MD9. The result is output to the first MD control device 24. The first MD control device 24 controls the first MD 7 based on the result of the calculation unit 26, and the second MD control device 25 anticipates a delay in the calculation time of the calculation unit 26 and performs the first MD control. The second MD 9 is controlled in synchronization with the device 24.

  Accordingly, the projection device 510 is supplied with illumination light whose excessive light amount is suppressed to the pixels, so that generation of unnecessary light due to excessive supply of illumination light is suppressed, and high-quality image display with higher contrast is achieved. It can be performed.

  The basic second MD9 control method, except for synchronization with the first MD control device 24, is a single DMD single-plate projection device that sequentially illuminates each time-divided RGB color. This can be the same as the control method of the image display DMD. Therefore, the image display apparatus according to the present invention can be easily configured.

Although the brightness of each color is normalized for convenience and described as the same, in an actual discharge lamp, the brightness of each color is often different. In this case, for example, the time width of the ON light of each color in the second MD 9 is adjusted by the time division control so that the projected image has a desired brightness and color balance, and the time division control of the ON light of the second MD 9 is performed. The second MD 9 may be set to be illuminated by the time division control of the ON light of the first MD in synchronization.
(Second Embodiment)
FIG. 5 shows another example of the projection apparatus according to the present invention. The projection device 600 includes a light emitting diode (LED: Light Emitting Diode) (hereinafter referred to as an LED group 20) arranged in a matrix, which is an illuminating means, and a cross dichroic mirror in the order in which light emitted from the LED group 20 travels. 21, a relay optical system 22, a second MD 9 that is an image display means, and a projection lens 10. The optical paths from the LED groups 20 a, 20 b, and 20 c are combined by a cross dichroic mirror 21. Since the LED group 20 and the second MD 9 are arranged in a substantially conjugate relationship via the relay optical system 22, the second MD 9 can be efficiently illuminated by the LED group 20.

  The LED group 20 includes, for example, an LED group 20a composed of red LEDs, an LED group 20b composed of green LEDs, and an LED group 20c composed of blue LEDs. The red LED, green LED, and blue LED are light control elements. The LEDs of each color are arranged in a matrix on a single plane to constitute LED groups 20a, 20b, and 20c that are light source light quantity changing means.

  Since the LED that is the light control element has a fast response speed of light emission, the discharge lamp 1 described in the first embodiment is obtained by combining the light amount of each color emitted from the LED group 20 with the cross dichroic mirror 21 by time-sharing control. The function equivalent to that of the illumination means including the color wheel 4 and the first MD 7 can be achieved. That is, in the LED group 20, the light emitted from the color wheel 4 is imitated, and, for example, red LED, green LED, and blue LED are sequentially driven in order in order to emit light. By doing in this way, the light synthesize | combined by the cross dichroic mirror 21 and radiate | emitted can be made into three colors divided | segmented equally as FIG.2 (b). Further, like the first MD7 light control element corresponding to the second MD9 pixel described in the first embodiment, when each color LED is driven, it is synchronized with the ON state of the second MD9 pixel. The LED corresponding to the pixel is turned on. In this way, the RGB color radiated by the LED group 20 is subjected to the color time-division control of the light emitted from the LED group 20 in the same manner as in the color wheel 4 and the first MD7 described in the first embodiment. The pixels of the second MD9 can be illuminated in synchronization with the image formation of each color by the MD9.

  In the projection device 600, as shown in FIG. 6, a plurality of pixels (9 pixels in the drawing) on the second MD 9 correspond to one LED of each color LED group 20a, 20b, 20c. . An example of the control method of the LED group 20 and the second MD 9 in this case will be described with reference to FIG. For ease of explanation, the red LED group 20a in the LED group 20 is taken as an example. One specific LED 7k of the LED group 20a corresponds to a pixel group L composed of a plurality of specific pixels of the second MD9. The LED 7k is controlled to emit light so as to satisfy the largest light amount (ON light time width) among the pixels of the pixel group L. For example, as shown in FIG. 7, when the longest time width of the ON light in the specific pixel group L (9 pixels in the drawing) of the second MD9 is 25, the LED 7k of the LED group 20a corresponding thereto Controls the light emission assuming that the time width of ON light of all nine pixels of the pixel group L of the second MD9 to be illuminated is 25. A pixel that requires a light amount whose ON light time width is less than 25 can be easily adjusted by time-sharing control by the pixel itself. The other green LED group 20b and blue LED group 20c may be controlled to emit light in the same manner as the red LED group 20a.

  By controlling the amount of light that illuminates the pixel group illuminated by one LED of each color as described above, while ensuring that the amount of light that illuminates the pixel that requires the most amount of light in the pixel group is not short, It is possible to suppress as much as possible the amount of light that illuminates these pixels so as not to be excessively supplied.

  The projection device 600 is provided with a calculation unit 26a. Based on the image data from the image data supply unit 23, the calculation unit 26a determines the time width of the ON light in one LED of the LED group 20 corresponding to the plurality of pixel groups of the second MD9, and the result is Output to the LED controller 28. The LED control device 28 controls the LED group 20 based on the result of the calculation unit 26a, and the second MD control device 25 synchronizes with the LED control device 28 in anticipation of the calculation time delay of the calculation unit 26a. 2 MD9 is controlled. The basic second MD9 control method, except for synchronization with the LED control device 28, is for displaying one image in a conventional DMD single-plate type projector that is sequentially illuminated in time-divided RGB colors. This can be the same as the DMD control method. Therefore, the image display apparatus according to the present invention can be easily configured.

  In the projection apparatus 600 described so far, by projecting a pixel group composed of a plurality of pixels with one LED for each color, a projected image while reducing the number of LEDs constituting the LED group 20 and reducing the cost. The amount of light of each color necessary for forming the light is supplied as illumination light without excess or deficiency. For this reason, generation | occurrence | production of the unnecessary light by the excessive supply of illumination light is suppressed, and a high quality image display with a higher contrast can be performed.

The LED described above may be a laser diode (LD), and it is easy to perform synchronous control with the second MD 9 that is an image display means by directly controlling light emission of the LED or LD that has a fast response speed. This is preferable because it is possible. In addition, since no components such as a color wheel are required, the image display device can be configured simply.
(Third embodiment)
FIG. 8 shows an example of the configuration of a projection apparatus 700 according to the present invention. A condensing optical system 2 is arranged in the traveling direction of light (white light) emitted from the discharge lamp 1. In the light emission direction of the light collecting optical system 2, a color wheel 4 for converting the light emitted from the light collecting optical system 2 into each color of R (red) G (green) B (blue) is disposed. A rod integrator 5 is disposed in the traveling direction of light transmitted through the color wheel 4, and a relay optical system 6 is disposed in the light emitting direction of the rod integrator 5. An input / output prism 40 is disposed in the light emission direction of the relay optical system 6.

  The input / output prism 40 is disposed with a first prism 40a on which light emitted from the relay optical system 6 enters and a third prism 40c on which light is emitted to the projection lens 10 and an air gap therebetween. Prism 40b.

  A first MD 7 and a second MD 9 are arranged in the light emission directions of the first prism 40a and the second prism 40b, respectively. As described in the first and second embodiments, it is possible to obtain illumination light whose light amount is adjusted to the pixels of the second MD9 by the first MD7. The OFF light of the first MD7 (light reflected in the direction not illuminating the second MD9) is totally reflected once in the second prism 40b, then enters the third prism 40c, and then the third prism After being totally reflected in the prism 40c, it is emitted from the third prism 40c.

  The ON light of the first MD7 (the light reflected in the direction of illuminating the second MD9) is the air gap between the first prism 40a and the second prism 40b, and the second prism 40b and the third prism 40c. After being totally reflected by the air gap therebetween, the light is emitted from the second prism 40b and reaches the second MD9. Further, the OFF light of the second MD 9 passes through the second prism 40b and the third prism 40c and is emitted from the third prism 40c. The ON light of the second MD 9 that displays an image passes through the second prism 40 b and the third prism 40 c, reaches the projection lens 10, and the image formed by the second MD 9 by the projection lens 10 is projected onto the screen. Is done.

  The first MD7, the second MD9, and the input / output prism 40 can be configured as shown in FIG. In this way, by adopting a configuration in which the first MD 7 excludes OFF light so that it does not enter the projection lens 10 as much as possible, a decrease in contrast can be further suppressed. Further, even in a system with a large amount of heat of illumination light and a system with a small lens back where the OFF light hits the projection lens 10, the thermal load due to the OFF light irradiation on the input / output prism 40 side of the projection lens 10 is reduced. Since it is possible to use a heat-sensitive plastic member for the final lens frame, it is possible to reduce the cost.

  When the first MD7 and the second MD9 are not in a conjugate relationship as shown in FIGS. 8 and 9, the plurality of light control elements of the first MD7 illuminate the plurality of pixels of the second MD9. Is possible. In this case as well, the light control element may radiate the amount of illumination light corresponding to the pixel having the largest luminance value among the corresponding pixels.

  In the projection apparatus 700, as described in the first and second embodiments, the light control element of the first MD7 has the relationship as described above for illuminating the pixel of the second MD9, and each light control element In addition, by performing time-sharing control in synchronism with the pixels, excessive supply of the amount of light for illuminating the pixels of the second MD9 can be suppressed and generation of unnecessary light can be reduced, so that high-quality image display with higher contrast can be performed. Can do.

It is a figure which shows an example of the projection apparatus concerning this invention. It is a figure explaining the modulation | alteration of the light quantity radiated | emitted from a discharge lamp. It is a figure which shows a mode that the light control element of 1st DMD and the pixel of 2nd DMD respond | correspond one-to-one. It is a figure which shows the example of the projection apparatus made into the structure by which the light radiated | emitted from the specific several light control element of 1st DMD is irradiated to the specific 1 pixel of 2nd DMD. It is a figure which shows an example of the projection apparatus concerning this invention. It is a figure which shows a mode that one LED of each color LED group and the some pixel on 2nd DMD respond | correspond. When one LED of each color LED group corresponds to a plurality of pixels on the second DMD, it is a diagram illustrating a method of determining the amount of light that illuminates each pixel. It is a figure which shows an example of the projection apparatus concerning this invention. It is a figure which shows another structural example of the input-output prism shown in FIG. It is a figure which shows the structure of a liquid crystal projector as a prior art example. In a liquid crystal projector as a conventional example, it is a figure which shows typically the state of the light quantity emitted from a discharge lamp until it inject | emits from a projection lens.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Discharge lamp 2 Condensing optical system 3 UV / IR cut filter 4 Color wheel 5 Rod integrator 6, 8, 22 Relay optical system 7 1st MD
7 '1st liquid crystal element 9 2nd MD
9 '2nd liquid crystal element 10 Projection lens 11 PS conversion optical element 12 1st fly eye integrator 13 2nd fly eye integrator 14 Relay lens 15a, 15b Dichroic mirror 16 Mirror 17a, 17b, 17c Field lens 18a-18f Polarization Plate 19 Cross prism 20, 20a, 20b, 20c LED group 21 Cross dichroic mirror 23 Image data supply unit 24 First MD control unit 25 Second MD control unit 26, 26a Calculation unit 28 LED control unit 40 Input / output prism 500 , 510, 600, 700 Projector

Claims (10)

Illumination means for emitting light of multiple colors;
In an image display device comprising image display means for modulating light emitted from the illumination means,
The illumination means includes a light source light quantity control means in which a plurality of light control elements that emit light by controlling the light quantity by time division control are arranged in a matrix in one plane,
The image display means includes a plurality of pixels arranged in a matrix within one plane, and a pixel that modulates the amount of light emitted from the illumination means in synchronization with time-division control of the light control element,
The image display device, wherein the light source light quantity control means and the image display means have a predetermined relationship in which light emitted from a specific light control element illuminates a specific pixel. The illumination means includes a discharge lamp,
A color wheel that receives light from the discharge lamp and sequentially decomposes and outputs the light into a plurality of colors; and
The light source light quantity control means includes a matrix of light reflection angle variable mirror elements that time-division-control light emitted from the color wheel by selectively determining a reflection direction according to an input illumination signal. The image display device according to claim 1, wherein the image display devices are mirror devices arranged in a shape. The image display device according to claim 1, wherein the light control element is a light emitting diode or a laser diode. In the image display means, a light reflection angle variable mirror element that controls time-division of light emitted from the illumination means by selectively determining a reflection direction according to an input video signal is formed in a matrix in a plane. The image display device according to claim 1, wherein the image display device is a mirror device arranged in an array. The number of the light control elements in the light source light amount control means is equal to the number of the pixels in the image display means,
5. The predetermined relationship is a relationship in which light emitted from one light control element illuminates one of the pixels corresponding to the light control element on a one-to-one basis. The image display device according to any one of the above. The number of the light control elements in the light source light quantity control means is less than the number of the pixels in the image display means,
The predetermined relationship is a relationship in which light emitted from one light control element illuminates a plurality of the pixels corresponding to the light control element. The image display device according to one item. 5. The predetermined relationship is a relationship in which light emitted from a plurality of the light control elements illuminates one or more pixels corresponding to the light control elements. The image display device according to any one of the above. The image display apparatus according to claim 1, wherein the light source light quantity control unit and the image display unit have a substantially conjugate relationship. 9. The light quantity emitted by the light control element in the light source light quantity control means is a light quantity corresponding to a pixel having the highest luminance value among pixels corresponding to the light control element. The image display device described. An image display device according to any one of claims 1 to 9,
A projection apparatus comprising: a projection optical system that projects modulated light from the image display apparatus onto a projection surface.

Images