JP2004302253A - Projection type display apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projection type display device which has high luminance and a uniform luminance distribution and is inexpensive. <P>SOLUTION: The projection type display device 10 is equipped with: a light source 11, an optical modulating means 16 which modulates the light from the light source 11; and a projecting means 17 which projects the light modulated by the optical modulating means 16. The optical modulating means 16 is equipped with a uniform lighting means 12 that comprises a light valve which has an array of pixels modulating color lights of different colors and is driven by pixels corresponding to the respective color lights and make uniform the illuminance of the luminous flux from the light source, a color separating means on which a portion of the luminous flux from the light source 11 is made incident and which separates the luminous flux into color lights of different colors, a 1st reflecting means of reflecting luminous flux which is not made incident on the color separating means, and a 2nd reflecting means 23 of reflecting the luminous flux reflected by the 1st reflecting means to the color separating means. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a projection display device, and more particularly to a configuration of a high-brightness and low-cost projection display device.
[0002]
[Prior art]
2. Description of the Related Art A projection display device that combines image light using a light modulation device such as a liquid crystal light valve and enlarges and projects the combined image light onto a screen through a projection optical system including a projection lens or the like has been conventionally known.
FIG. 5 is a schematic configuration diagram illustrating an example of a projection display device. In the figure, reference numeral 110 denotes a light source, 120 denotes a light beam correction lens, 130 denotes a light beam correction lens array, 140 denotes a prism array, 150 denotes a liquid crystal display panel (light modulation unit), and 160 denotes a projection lens.
[0003]
As shown in FIG. 5, the white light emitted from the light source 110 is converted into parallel light by the light flux correction lens 120 and the light flux correction lens array 130, and the parallel light is red (hereinafter referred to as red) having a different wavelength range by the prism array 140. The light is separated into light fluxes R, G, and B of green (hereinafter, described as G) and blue (hereinafter, described as B). These luminous fluxes R, G, and B are made incident on the respective pixel display portions of the single liquid crystal display panel 150, and the light emitted from the liquid crystal display panel 150, that is, the color image light is projected on the screen 170 by the projection lens 160. (For example, see Patent Document 1).
[0004]
[Patent Document 1]
JP-A-7-287206 (Pages 3-4, Figures 1 and 2)
[0005]
[Problems to be solved by the invention]
As described above, in the conventional projection display device, the light collimated by the light beam correcting lens 120 and the light beam correcting prism 130 is split by the prism array 140. However, since the light beam correcting lens 120 and the light beam correcting prism 130 do not function to equalize the illuminance of light, there is a problem that a color image having a uniform luminance distribution cannot be projected on the screen 170.
[0006]
Further, since many optical components such as the light beam correcting lens 120, the light beam correcting prism 130, and other lens arrays are used, there is a problem that the configuration of the apparatus is complicated and it is difficult to reduce the cost.
[0007]
The present invention has been made to solve the above-described problems, and has as its object to provide an inexpensive projection display device having a high luminance, a uniform luminance distribution, and the like.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, a first projection type display device according to the present invention comprises a light source, a light modulation unit for modulating light from the light source, and a projection unit for projecting light modulated by the light modulation unit. Wherein the light modulating means comprises a light valve in which pixels for modulating color lights of different colors are arranged, and a light valve driven for each pixel corresponding to each color light is provided. Uniform illumination means for making the illuminance of the light beam uniform, a part of the light beam from the light source being incident thereon, a color separating means for separating the light beam into color lights of different colors, and a light beam not incident on the color separating means. It is characterized by comprising: first reflecting means for reflecting light; and second reflecting means for reflecting the light beam reflected by the first reflecting means in the direction of the color separation means.
[0009]
That is, in the projection type display device of the present invention, the luminous flux emitted from the light source is uniformed in luminance distribution by the uniform illuminating means, and one of the luminous fluxes is separated into different color lights by the color separating means to correspond to each color light. The light valve that forms light modulating means is driven for each pixel corresponding to each color light and is combined with the projected image. Further, the light flux that has not entered the color separation means is reflected by the first reflection means and propagates in the opposite direction, and is reflected again by the second reflection means in the direction of the color separation means to contribute to the projection of an image. That is, the luminance of the light beam incident on the color separation means can be higher than the luminance of the light beam emitted from the light source.
Therefore, unlike the single-panel projection display device described in the related art in which parallel light is split by a prism using a lens array, a projection display device with illumination of uniform brightness on a screen is realized. be able to. Further, a complicated lens array is not required, and the illumination optical system can be simplified. Therefore, the number of parts can be greatly reduced, and the device configuration can be simplified, so that cost reduction can be achieved.
[0010]
To realize the above configuration, more specifically, a transparent rod-shaped light guide or a tubular light guide having an inner surface as a reflection surface can be used as the uniform illumination means. A fly-eye integrator is well known as a uniform illumination means used in a projection display device. However, in the case of a fly-eye integrator, two fly-eye lenses in which a large number of lenses are arranged in parallel are required, and cost reduction is difficult to achieve. Has become. On the other hand, the rod integrator, unlike the fly-eye integrator, has a simple configuration such as a transparent rod-shaped light guide or a tubular light guide whose inner surface is a reflection surface. Therefore, the device configuration can be simplified without the need for complicated components such as a fly-eye integrator, and the cost can be reduced.
[0011]
As the rod integrator, a rod integrator whose vertical and horizontal dimensions substantially match the vertical and horizontal dimensions of the light modulation unit can be used.
Since the vertical and horizontal dimensions of the rod integrator substantially match the vertical and horizontal dimensions of the light modulating means, the distance between the rod integrator and the light modulating means is reduced so that the light flux emitted from the rod integrator does not leak to the light modulating means. Light can be incident with a uniform luminance distribution.
In other words, there is no need to use a light condensing means or the like conventionally used for efficiently guiding the light beam emitted from the rod integrator to the light modulating means, so that the number of parts can be reduced and the cost can be reduced.
[0012]
It is preferable that the projection display device includes a parallel light converting unit that converts a light beam from a light source into parallel light.
With the provision of the parallel light converting means, the light emitted from the light source can become parallel light and enter the color separating means. Then, the light separated by the color light separation means enters the pixels corresponding to each color light, so that an image having a uniform luminance distribution can be projected.
For example, if the light beam incident on the color separation unit is not parallel light, the separated color light beams may be incident on pixels other than the pixel corresponding to each color light, so that the brightness of the image becomes non-uniform, Or cause color mixing.
[0013]
A reflecting mirror can be used as the second reflecting means, and is desirably provided on the end face of the uniform illumination means on the light beam incident side.
Since the reflecting mirror is provided on the light-incident side end face of the uniform illuminating means, not only the light reflected by the first reflecting means is reflected toward the color separating means, but the reflected light is also reflected by the uniform illuminating means. When the light propagates through the light source, the luminance of the light flux incident from the light source is also uniformized, so that the luminance of the light flux emitted from the uniform illumination means becomes higher. That is, the light recycling rate increases.
[0014]
In addition, a reflector that reflects the light emitted from the light source toward the light modulating means can be used as the second reflecting means.
By using a reflector that reflects the light flux emitted from the light source in the direction of the light modulation means as the second reflection means, the light flux reflected by the first reflection means is reflected in the direction of the color separation means, The brightness of the light beam incident on the color separation means can be increased. At the same time, since it is not necessary to use a dedicated component for the second reflecting means, the number of components can be reduced, the device configuration can be simplified, and the cost can be reduced.
[0015]
A spectral prism can be used as the color separating means, and a reflecting film can be used as the first reflecting means.
By using a spectral prism having a simple shape as the color separation means, a relatively inexpensive manufacturing method such as press forming can be used, and cost reduction can be achieved. Further, even if photolithography, which is classified as an expensive manufacturing method, is used, since the shape is simple, the number of manufacturing steps is small and the cost is not increased so that the cost can be reduced.
[0016]
It is desirable that the spectral prism is formed such that the size of the light beam incident surface substantially matches the size of one pixel of the light modulating means when viewed from the direction of the light beam incident from the light source.
The light beam incident on the light splitting prism from the light beam incident surface is split because the refractive index differs depending on the color light of each color. Since the split color light has a size in the direction perpendicular to the incident direction of the light beam incident on the splitting prism substantially equal to the size of one pixel, the split color light is also incident on each pixel of the light modulation means. It has a dimension of one pixel in the perpendicular direction. Therefore, each color light is incident on the corresponding pixel, and it is possible to prevent color mixture by being incident on another pixel, and it is possible to make the luminance distribution of the color light incident on each pixel uniform. As a result, the luminance distribution of the projected image can be made uniform.
[0017]
The size of the combined light beam incident surface and the reflective film of the adjacent spectral prism may be formed so as to substantially match the combined size of a plurality of pixels corresponding to each color light when viewed from the light beam incident direction from the light source. desirable.
Since the size obtained by combining the light incident surface of the adjacent spectral prism and the reflective film and the size obtained by combining a plurality of pixels corresponding to each color light are formed to substantially match, the light is split by the spectral prism. The respective color lights are respectively incident on the corresponding pixels. In addition, since each color light separated by the other spectral prism enters each pixel corresponding to the other spectral prism, the color light separated by the other spectral prism does not enter other pixels. Color mixing can be prevented. At the same time, since the color light can be uniformly incident on all the pixels, the luminance distribution of the projected image can be made uniform.
[0018]
It is preferable that a deflecting unit is provided to guide each color light separated by the color separating unit to a pixel corresponding to each color light of the light modulating unit.
By providing the deflecting means, each color light is guided to the corresponding pixel, so that the brightness distribution of the projected image can be easily made uniform. For example, conversely, when a part of a certain color light is incident on a pixel having no correspondence, color mixing occurs, and the amount of light incident on the pixel increases to increase the luminance. Further, in a pixel to which a certain color light is to be incident, the amount of light is reduced, the luminance is reduced, and the luminance distribution of the image becomes non-uniform.
[0019]
As the above-mentioned deflecting means, it is possible to use a prism arranged on a set of pixels corresponding to different colors on the light modulating means.
By using a prism having a simple shape as the deflecting means, as described above, it is possible to use an inexpensive manufacturing method such as press forming or to use an expensive manufacturing method such as photolithography to reduce the cost. And cost reduction can be achieved.
[0020]
It is desirable to provide a reflection polarization unit that transmits polarized light polarized on one side and reflects polarized polarized light on the other side of the light incident from the light source.
Providing the reflection polarization means allows the light emitted from the light source to contribute to display on the light valve, while transmitting polarized light to one side and reflecting polarized light to the other side. When the reflected polarized light is reflected by the reflecting means or the like, a part of the polarized light is rotated to become the polarized light polarized to one side, and can be transmitted through the reflecting polarizing means, thereby increasing the light use efficiency. As a result, the brightness of the light beam incident on the color separation means can be increased.
[0021]
BEST MODE FOR CARRYING OUT THE INVENTION
[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a schematic diagram showing an overall configuration of a projection display device 10 according to the present embodiment as viewed from above. In FIG. 1, reference numeral 11 denotes a light source, 12 denotes a rod integrator (uniform illumination means), 13 denotes a condenser lens system (parallel light conversion means), 14 denotes a reflection type polarizing plate (reflection polarization means), 15 denotes a prism system, and 16 denotes a liquid crystal. A light valve (light modulating means) 17 is a projection lens (projecting means).
[0022]
As shown in FIG. 1, the light source 11 of the projection display device 10 according to the present embodiment includes a lamp 21 such as a metal halide and a reflector 22.
As the rod integrator 12, a transparent rod-shaped light guide (for example, a glass rod) or a tubular light guide having an inner surface as a reflection surface (for example, a kaleidoscope in which a plurality of reflection mirrors are arranged in a tubular shape with the inside facing inward) ) Is used. A reflection mirror (second reflection means) 23 is provided on the incident end face of the rod integrator 12 so that the reflection face faces the emission side end face, and light from the light source 11 is substantially at the center of the reflection mirror 23. An opening 24 that enters the integrator 12 is provided.
[0023]
The condenser lens system 13 is provided with a condenser lens 25a and a condenser lens 25b so that light incident from the rod integrator 12 is incident on the reflective polarizer 14 as parallel light.
As shown in FIG. 2, the prism system 15 includes a color separation / reflection unit 26 provided between the reflective polarizer 14 and the liquid crystal light valve 16, and a correction prism (deflection unit) provided on the liquid crystal light valve 16. 27 are arranged in a matrix. The color separation / reflection unit 26 includes a spectral prism (color separating unit) 28 and a reflective film (first reflecting unit) 29 disposed adjacent to the spectral prism 28.
[0024]
The spectroscopic prism 28 has a vertical surface (light incident surface) 28a formed perpendicularly to the system optical axis C on the side of the reflective polarizing plate 14 and having a size substantially matching the size of one pixel described later, and a liquid crystal light valve. On the 16 side, an inclined surface 28b inclined with respect to the system optical axis C is arranged. The inclination angle of the inclined surface 28b is set so that the color lights R, G, and B separated by the spectral prism 28 correspond to one pixel on the liquid crystal light valve 16, respectively. The reflection film 29 is formed to have a size substantially equal to a size obtained by combining two pixels described later, and is arranged with its reflection surface facing the reflective polarizing plate 14.
Further, the correction prism 27 is formed to have a size that substantially matches the size of three pixels described later, and an inclined surface 27a having the same inclination as the inclined surface 28b is provided on the reflective polarizing plate 14 side.
[0025]
The liquid crystal light valve 16 uses a TN (Twisted Nematic) mode active matrix transmission type liquid crystal cell using a thin film transistor (hereinafter abbreviated as TFT) as a pixel switching element.
The liquid crystal light valve 16 includes substrates 31a and 31b disposed on the prism system 15 side and the projection lens 17 side, a common electrode 32 provided on the substrate 31a, and a pixel (pixel electrode) 33 provided on the substrate 31b. It comprises a thin film transistor (not shown) for controlling the voltage between the common electrode 32 and the pixel 33, and a liquid crystal 34 sealed between the common electrode 32 and the pixel 33.
In the pixel 33, a pixel 33r corresponding to R, a pixel 33g corresponding to G, and a pixel 33b corresponding to B form one set, and this set and the correction prism 27 are arranged correspondingly.
[0026]
Next, the operation of the projection display device 10 having the above configuration will be described.
As shown in FIG. 1, the white light emitted to the surroundings by the emission of the lamp 21 is reflected by the reflector 22, condensed toward the opening 24 of the reflection mirror 23, and is incident on the rod integrator 12. You. The white light that has entered the rod integrator 12 repeats internal reflection within the rod integrator 12, and when emitted from the exit end face, has uniform illuminance and exits from the exit side end face.
The white light emitted from the rod integrator 12 becomes parallel light by transmitting through the condenser lenses 25a and 25b, and is emitted toward the reflective polarizer.
[0027]
As shown in FIG. 2, one of the p-polarized light Lp and the s-polarized light Ls (linearly polarized light) (for example, the p-polarized light Lp) included in the white light goes straight as it is on the reflective polarizer 14. And the other (for example, s-polarized light Ls) is reflected and propagates in the opposite direction (to the condenser lens 25a side).
Of the p-polarized light Lp transmitted through the reflective polarizer 14, the p-polarized light Lp incident on the vertical surface 28 a of the spectral prism 28 of the prism system 15 is white light in which color lights of various wavelengths are mixed. The light is color-separated by utilizing the difference in the refractive index of the liquid crystal and is emitted to the liquid crystal light valve 17 side. This will be described with reference to FIG. 2. Since the refractive indices of the color lights R, G, and B are R, G, and B in ascending order, the color lights separated by the spectral prism 28 bend with respect to the system optical axis C. The light is emitted from the spectral prism 28 in the order of R, G, and B in ascending order.
Further, the white light flux incident on the spectral prism 28 has a dimension substantially corresponding to the dimension of one pixel 33 in a direction perpendicular to the system optical axis C, and even if the light flux is separated into the respective color lights R, G, B, the The dimension in the direction perpendicular to the system optical axis C substantially matches the dimension of one pixel 33.
The p-polarized light Lp incident on the reflective film 29 is reflected and propagates in the opposite direction (to the reflective polarizer 14).
The color lights R, G, and B, which are color-separated by the spectral prism 28 and emitted in different directions for the respective color lights R, G, and B, propagate in the propagation direction by the correction prism 27 having the inclined surface 27a having the same inclination angle as the inclined surface 28b. Is changed to parallel light parallel to the system optical axis C and having a width corresponding to one pixel 33.
[0028]
The color lights R, G, B converted into parallel lights by the correction prism 27 are incident on the pixels 33r, 33g, 33b of the liquid crystal light valve 16 corresponding to the respective color lights R, G, B. Here, for example, when the pixel electrode is off, p-polarized light incident on the liquid crystal light valve 16 is converted (modulated) into s-polarized light and emitted, while when the pixel electrode is on, color light is cut off.
Since the liquid crystal light valve 16 is controlled and driven for each of the pixels 33r, 33g, and 33b corresponding to each color light, an image is synthesized by selectively modulating and transmitting each color light. The light emitted from the liquid crystal light valve 16 enters the projection lens 17 and is emitted toward the projection screen S as shown in FIG.
[0029]
Meanwhile, the s-polarized light Ls reflected by the reflective polarizer 14 propagates through the condenser lens system 13 toward the light source 11 and enters the rod integrator 12 as shown in FIG. As shown in FIG. 3, the s-polarized light Ls that has entered the rod integrator 12 reaches the incident end face of the rod integrator 12, and is partially reflected by the reflection mirror 23 and propagated again to the exit side of the rod integrator 12. The rest is emitted toward the light source 11 from the opening 24 of the reflection mirror, reflected by the reflector 22 and again enters the rod integrator 12. When the s-polarized light is reflected by the inner surface of the rod integrator 12, the reflective polarizer 14, the reflector 22, and the reflecting mirror 23, the polarization direction is rotated and a part of the s-polarized light is converted to p-polarized light. The converted p-polarized light transmits through the reflective polarizer 14 and contributes to increasing the brightness of the image projected on the screen S.
[0030]
Similarly, the p-polarized light Lp reflected by the reflection film 29 propagates toward the light source 11 up to the reflection mirror 23 or the reflector 22, is reflected there, and propagates again toward the liquid crystal light valve 16. The p-polarized light Lp, together with the white light emitted from the lamp 11 when propagating through the rod integrator 12, has a uniform luminance distribution, is emitted toward the condenser lens system 13, and is projected on the screen S. It contributes to higher brightness.
[0031]
According to the above configuration, the light reflected toward the light source 11 by the reflective polarizer 14 and the reflective film 29 is reflected toward the liquid crystal light valve 16 by the reflective mirror 23 and the reflector 22. Therefore, the luminance of light incident on the liquid crystal light valve 16 via the condenser lens system 13, the reflective polarizer 14, and the prism system 15 can be increased. That is, by selectively modulating each color light transmitted by the liquid crystal light valve 16, the luminance of the synthesized image can be increased, and the luminance of the image projected on the screen S can be increased.
[0032]
In addition, since the rod integrator 12 is provided between the light source 11 and the condenser lens system 13, a light beam having a non-uniform brightness distribution and unevenness at the time of emission from the light source 11 is removed by the rod integrator 12. The luminance distribution of the light beam can be made uniform. As a result, a light beam having a uniform luminance distribution can be made incident on the liquid crystal light valve 16, and the image synthesized by the liquid crystal light valve 16, that is, the luminance distribution of the image projected on the screen S can be made uniform.
[0033]
Since the spectral prism 28 is formed to have a size that substantially matches the size of one pixel 33, and the reflective film 29 is formed to have a size that substantially matches the size obtained by combining the two pixels 33, the pixels 33r and 33g corresponding to each color light are provided. , 33b can be made to enter each color light of the width of the pixel 33, and the luminance distribution of each pixel 33 can be made uniform.
Further, since the combined size of the adjacent spectral prism 28 and the reflective film 29 is equal to the combined size of the pixels 33r, 33g, and 33b corresponding to each color light, the pixels 33r, 33g, and 33b have only the corresponding color light. Does not enter. In other words, the color light split into the other spectral prisms 28 does not enter, so that the color light can be made to uniformly enter all the pixels 33, so that the luminance distribution of the projected image can be made uniform.
[0034]
Further, as a method of manufacturing the spectral prism and the correction prism, since their shapes are simple, a relatively inexpensive manufacturing method such as press forming can be used, and cost can be reduced. Further, even if photolithography classified as an expensive manufacturing method is used, since the shape is simple, the number of manufacturing steps is small, so that the cost is not so high and the cost can be reduced.
[0035]
[Second embodiment]
Next, a second embodiment of the present invention will be described with reference to FIG.
The basic configuration of the projection display device of the present embodiment is the same as that of the first embodiment, but differs from the first embodiment in that a condenser lens system and the like are not provided. Therefore, in the present embodiment, only the vicinity of the rod integrator will be described with reference to FIG. 4, and description of the light source and the like will be omitted.
[0036]
FIG. 4 is a diagram showing a schematic configuration of the projection display device 50 in the present embodiment.
In the projection type display device 50, a rod integrator (uniform illumination means) 51 is disposed between the light source 11 and the reflective polarizer 14, as shown in FIG. Or a tubular light guide having an inner surface as a reflection surface. The cross section of the rod integrator 51 has the same shape from the incident end face 52 to the emission end face 53, and the vertical and horizontal widths of the cross section are the same as those of the liquid crystal light valve 16.
Further, the distance between the rod integrator 51, the reflective polarizer 14, the prism system 15, and the liquid crystal light valve 16 is narrowed.
[0037]
In the projection display device 50 having the above configuration, as shown in FIG. 4, white light emitted from the lamp 21 is reflected by the reflector 22 and is incident on the incident surface 52 of the rod integrator 51. The white light incident on the rod integrator 51 is repeatedly reflected on the inner surface of the rod integrator 51, and the luminance is made uniform when the white light is emitted from the emission end face 53.
Further, since the rod integrator 51 makes the luminance distribution of the light beam uniform by the above-described operation, the angle of the light beam incident on the incident end face 52 is maintained until the light is emitted from the emission end face 53.
[0038]
The white light flux emitted from the rod integrator 51 is transmitted by the reflective polarizer 14 so that the p-polarized light Lp is transmitted, and the s-polarized light Ls is reflected and propagates in the opposite direction (toward the light source 11) as parallel light. The transmitted p-polarized light Lp enters the prism system 15, and a part of the p-polarized light Lp is separated into light of different colors and enters the liquid crystal light valve 16. The p-polarized light Lp that has not been split is reflected and propagates in the opposite direction (to the light source 11) as parallel light.
The reflected s-polarized light Ls and p-polarized light Lp pass through the rod integrator 52, enter the reflector 55, are reflected by the reflector 55, and propagate again toward the liquid crystal light valve 16.
[0039]
In addition, since the distance from the rod integrator 51 to the liquid crystal light valve 16 is short, and the vertical and horizontal widths of the rod integrator 51 are substantially equal to the vertical and horizontal widths of the liquid crystal light valve 16, the light flux emitted from the rod integrator 51 does not leak. Light is incident on the entire surface of the liquid crystal light valve 16 with uniform luminance.
[0040]
According to the above configuration, the light beam emitted from the light source 11 and having a uniform luminance distribution enters the liquid crystal light valve 16 without leaking, without using the condenser lens system 13 used in the first embodiment. Can be done. Therefore, the number of parts can be reduced, and the cost can be reduced.
[0041]
Note that the technical scope of the present invention is not limited to the above-described embodiment, and various changes can be made without departing from the spirit of the present invention.
For example, in the above-described embodiment, a description has been given of the case where the spectral prism 28 is used to separate white light into color light. However, the present invention is not limited to the case where the spectral prism 28 is used. And various other spectroscopic means.
[0042]
Further, in the above-described embodiment, the uniform illumination means has been described by using the rod integrator 12 having the same shape in cross section from the incident end face to the exit end face. However, the present invention can be applied to a rod integrator having a tapered shape in which the cross section of the rod integrator increases from the incident end face to the exit end face.
[0043]
In this case, light incident from the incident end surface of the rod integrator and reflected on the outer peripheral surface of the rod integrator has an incident angle and a reflection angle equal to the outer peripheral surface. However, since the outer peripheral surface is inclined so as to open outward toward the emission side, the light reflection angle with respect to the central axis of the rod integrator is smaller than the incident angle. Therefore, the light emitted from the rod integrator becomes light closer to parallel light, so that it is possible to reduce the precision of other components regarding the parallelization of light and reduce costs.
[0044]
Further, in the above-described embodiment, the description has been made by applying the correction prism 27 as the correction means. However, the present invention is not limited to the correction prism 27, and one pixel 33 of the liquid crystal light valve 16 may be used. The present invention can also be applied to a microlens arrayed one by one, or a microlens using both the correction prism 27 and the microlens at the same time.
When the correction prism 27 and the microlens 81 are used at the same time, the microlens 81 and the correction prism 27 may be arranged on the liquid crystal light valve 16 in this order. The micro lenses 81 may be arranged in this order.
[Brief description of the drawings]
FIG. 1 is a schematic diagram illustrating a projection display device according to a first embodiment of the present invention.
FIG. 2 is a schematic diagram showing a light modulation unit according to the first embodiment of the present invention.
FIG. 3 is a schematic diagram illustrating a light source, a uniform illumination unit, and a reflection unit according to the first embodiment of the present invention.
FIG. 4 is a schematic diagram illustrating a projection display device according to a second embodiment of the present invention.
FIG. 5 is a schematic configuration diagram illustrating an example of a conventional projection display device.
[Explanation of symbols]
Reference Signs List 10 projection display device, 11 light source, 12 rod integrator (uniform illumination means), 13 condenser lens system (parallel light conversion means), 14 reflection type polarizing plate (reflection polarization means), 16 liquid crystal light valve (light modulation means), Reference Signs List 17 projection lens (projection means), 22 reflector, 23 reflection mirror (second reflection means), 27 correction prism (deflection means), 28 spectral prism (color separation means), 28a vertical plane (beam entrance plane), 29 reflection Film (first reflection means),
33 pixels, 51 rod integrator (uniform illumination means)

Claims (12)

A projection display device including a light source, light modulation means for modulating light from the light source, and projection means for projecting light modulated by the light modulation means,
The light modulating means includes pixels that modulate color lights of different colors are arranged, and includes a light valve that is driven for each pixel corresponding to each color light,
Uniform illumination means for uniformizing the illuminance of the light flux from the light source,
A part of a light beam from the light source is incident, and a color separation unit that separates the light beam into color lights of different colors,
First reflecting means for reflecting a light beam not incident on the color separating means;
And a second reflecting means for reflecting the light beam reflected by the first reflecting means in the direction of the color separating means. 2. The projection display device according to claim 1, wherein the uniform illuminating means is a rod integrator formed of a transparent rod-shaped light guide or a tubular light guide having an inner surface as a reflection surface. 3. The projection display device according to claim 2, wherein the vertical and horizontal dimensions of the rod integrator substantially match the vertical and horizontal dimensions of the light modulating means. The projection display device according to claim 1, further comprising a parallel light conversion unit configured to convert a light beam from the light source into parallel light. The projection display device according to any one of claims 1 to 4, wherein the second reflection unit is a reflection mirror, and is provided on an end face of the uniform illumination unit on the light beam incident side. The light source includes a reflector that reflects light emitted from the light source toward the light modulation unit,
6. The projection type display device according to claim 1, wherein said reflector also serves as said second reflection means. 7. The color separation device according to claim 1, wherein the color separation unit is a spectral prism that separates a light beam into light beams of different colors, and the first reflection unit is a reflection film provided adjacent to the spectral prism. 3. The projection display device according to 1. 8. The projection display device according to claim 7, wherein a size of a light beam incident surface of one of the light splitting prisms substantially coincides with a size of one pixel of the light modulator when viewed from a light beam incident direction from the light source. . The combined size of the light incident surface and the reflective film of the adjacent spectral prism is substantially the same as the combined size of a plurality of pixels corresponding to each color light of the light modulating unit when viewed from the light incident direction from the light source. 9. The projection type display device according to claim 7, wherein the projection type display device and the projection type display device coincide with each other. 10. The projection display device according to claim 1, further comprising a deflecting unit that guides each color light separated by the separating unit to each pixel of the light modulating unit. 11. The projection display device according to claim 10, wherein the deflecting unit is a prism arranged for one set of pixels corresponding to different colors on the light modulating unit. 12. The light source according to claim 1, further comprising: a reflection polarization unit that transmits polarized light polarized to one side of the light incident from the light source and reflects polarized polarized light to the other side. Projection display device.

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