JP2002040416A - Single plate type liquid crystal projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a single plate type liquid crystal projector which makes it possible obtain bright projected images of high quality by enhancing light utilization efficiency while well maintaining color reproducibility. SOLUTION: A liquid crystal panel 13 of the color liquid crystal projector of a microlens-dichroic mirror system has a microlens array on the display region surface on an incident side. A reflector 2a and convex-concave cylindrical lenses 4, 5a convert the white natural light from the light source 1 to parallel light beams at compression rates varied by directions. The lens arrays 6, 7 make the spatial energy distribution of the parallel light beams uniform and the dichroic mirror 11 separates the light to a plurality of color light having angle differences. A PBS prism array 8 separates the incident light to two polarization components varying in polarization directions and a half wave plate 9 converts the one polarized light component to the polarized light component of the same polarization direction as the polarization direction of the other polarized light component.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a single-panel type liquid crystal projector, and more particularly to a microlens-dichroic mirror type color liquid crystal projector.

[0002]

2. Description of the Related Art A general single-panel type liquid crystal projector includes:
R (red), G (green), and B (blue) color filters are used. However, since the color filter absorbs light, the light use efficiency is reduced. Such a problem does not occur in the so-called microlens-dichroic mirror system because no color filter is used. According to this method, the light from the lamp is color-separated by a dichroic mirror into RGB light beams having different angles. Then, the light enters a microlens arranged for each pixel of the liquid crystal panel, and is condensed at a different position for each color light to illuminate each pixel of RGB. Various single-panel type liquid crystal projectors employing this method have been conventionally proposed (JP-A-11-32348, JP-A-11-202429, etc.).

[0003]

In a liquid crystal projector of a microlens-dichroic mirror type,
It is necessary to reduce the numerical aperture (NA) of each color light in the color separation direction. This is because if the NA is large, color mixture to adjacent pixels occurs, which causes a reduction in color reproducibility. On the other hand, if the NA is too small, only a part of the luminous flux from the lamp can be used for illumination in the color separation direction, and the light use efficiency is reduced.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and a single-panel type liquid crystal projector capable of obtaining a bright and high-quality projected image by increasing light use efficiency while maintaining good color reproducibility. The purpose is to provide.

[0005]

In order to achieve the above object, a liquid crystal projector according to a first aspect of the present invention comprises a light source for generating natural white light, and a shape conversion optic for converting light emitted from the light source to parallel light. System, a lens array type integrator optical system for equalizing the spatial energy distribution of the parallel light, and a color separation optical system for color-separating the light having the uniformized energy distribution into a plurality of color lights having an angle difference. A liquid crystal panel having a microlens array on the surface of the display area on the side where the respective color lights are incident, modulating light after passing through the microlens array, and performing image projection with the light modulated by the liquid crystal panel A projection lens, wherein the integrator optical system divides the incident light by a plurality of lens cells to form a plurality of light source images. A, and a second lens array having the same number of lens cells that conjugate each lens cell of the first lens array and the liquid crystal panel so as to form a pair with each lens cell of the first lens array; further,
A polarization separation element that separates incident light into two polarization components having different polarization directions so that a light source image formed by the first lens array is formed as a pair of light source images adjacent to each other having different polarization directions. To convert one of the polarization components into a polarization component having the same polarization direction as the other polarization component.
/ 2 wavelength plate, wherein the shape conversion optical system converts the light emitted from the light source into parallel light at different compression ratios depending on directions.

In a liquid crystal projector according to a second aspect of the present invention, in the configuration of the first aspect, the display area of the liquid crystal panel has a rectangular shape, and a direction corresponding to a long side and a direction corresponding to a short side of the rectangle. And the compression ratio is different, the direction in which the compression ratio is large, the long side of the display area of the liquid crystal panel,
The direction of color separation by the color separation optical system is parallel to the same plane, and the direction of separation into two polarization components by the polarization separation element is perpendicular to the plane. .

A liquid crystal projector according to a third aspect of the present invention is the liquid crystal projector according to the second aspect, wherein when the aspect ratio of the display area is α: β (α> β), the ratio of the compression ratio of the parallel light is 2α. / Β: 1.

According to a fourth aspect of the present invention, in the liquid crystal projector according to the first, second, or third aspect, the shape conversion optical system has a parabolic surface having a focal point at the light source position as a reflecting surface. A convex cylindrical lens that converges parallel light from the reflector in only one direction, and a concave cylindrical lens that returns light flux converged in only one direction by the convex cylindrical lens back to parallel light. I do.

According to a fifth aspect of the invention, in the liquid crystal projector according to the first, second, or third aspect, the shape conversion optical system has a focal point at the light source position and a curvature in a horizontal direction and a vertical direction. A reflector having a different anamorphic aspheric surface as a reflecting surface, and a concave cylindrical lens having lens surfaces with different curvatures in horizontal and vertical directions for converting a light beam from the reflector into parallel light. I do.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A single-panel type liquid crystal projector embodying the present invention will be described below with reference to the drawings. In addition,
The same or corresponding portions in the embodiments and the like are denoted by the same reference numerals, and repeated description will be appropriately omitted.

FIG. 1 is a sectional view showing an embodiment of a microlens-dichroic mirror type color liquid crystal projector. FIG. 1B shows a cross section of the entire liquid crystal projector as viewed from the long side (α) side of the liquid crystal panel (13) {that is, from a direction parallel to the short side (β)}. On the other hand, FIG. 1A shows a state in which the substantially L-shaped optical path shown in FIG. 1B is developed in one direction. That is, FIG. 1A shows the light source (1).
From the field lens (12) to the projection lens (14) are shown in a cross section from the direction perpendicular to the display surface of the liquid crystal panel (13). The cross section is viewed from the side (β) side (that is, from the direction parallel to the long side (α)).

In this liquid crystal projector, a light source (1), a reflector (2a), and a UV (ultraviolet ray) -IR
(infrared ray) cut filter (3), convex cylindrical lens (4), concave cylindrical lens (5a), first lens array (6), second lens array (7), PBS (polarizin
g beam splitter) prism array (8), half-wave plate
(9), superposition lens (10), dichroic mirror (1
1), a field lens (12), a liquid crystal panel (13), and a projection lens (14). Of these, reflectors (2
a) and convex and concave cylindrical lenses (4,5a) are shape conversion optics, first and second lens arrays (6,7) and superimposing lens (10) are lens array type integrator optics, PBS prism The array (8) and the half-wave plate (9) constitute a polarization conversion optical system, and the dichroic mirror (11) constitutes a color separation optical system.

Light source (1) is white natural light (randomly polarized light)
(For example, a metal halide lamp, an ultra-high pressure mercury lamp, etc.). In particular, an ultra-high pressure mercury lamp has a short arc and is therefore desirable for improving the lighting efficiency. The reflector (2a) has a paraboloid having a focus at the position of the light source (1) as a reflection surface. Therefore,
Light emitted from the light source (1) is converted into parallel light by the reflector (2a). The parallel light emitted from the reflector (2a) passes through the UV-IR cut filter (3), and then passes through the convex cylindrical lens (4) and the concave cylindrical lens (5).
Go through a).

The convex cylindrical lens (4) and the concave cylindrical lens (5a) act as an afocal system in the horizontal direction (H) with respect to the incident parallel light, but are merely parallel in the vertical direction (V). Acts as a flat plate. Therefore, the parallel light that has passed through the UV-IR cut filter (3) is converged only in the horizontal direction (H) by the convex cylindrical lens (4), and the converged light flux is again collimated by the concave cylindrical lens (5a). Is returned to. As described above, the light from the light source (1) is converted into parallel light compressed in the horizontal direction (H) by the shape conversion optical system including the cylindrical lenses (4, 5a) and the like.

The parallel light emitted from the concave cylindrical lens (5a) enters the first and second lens arrays (6, 7).
The first lens array (6) is formed by arranging rectangular lens cells substantially similar to the display area of the liquid crystal panel (13) in a two-dimensional array, and divides incident light by a plurality of lens cells. I do. Then, a plurality of light source images are formed in the vicinity of the second lens array (7) having the same array structure as the first lens array (6). The second lens array (7) has the same number of lens cells of the same shape that form a pair with each lens cell of the first lens array (6). Each lens cell of the first lens array (6) and the liquid crystal panel (13) are connected to the second lens array (7).
The illumination light is collected by the superimposing lens (10) such that the conjugate images of the lens cells of the first lens array (6) overlap on the liquid crystal panel (13) through the respective lens cells of the first lens array (6). Be lighted. In this way, the spatial energy distribution of the illumination light is made uniform, and the liquid crystal panel (13) is uniformly illuminated without waste.

The illumination light emitted from the second lens array (7) enters the PBS prism array (8). The PBS prism array (8) is a polarization separation element having a PBS prism in an array in the vertical direction (V). Each PBS prism has a polarization separation surface that separates incident illumination light into P-polarized light (transmitted light) and S-polarized light (reflected light), and a reflection surface that reflects S-polarized light in the same direction as P-polarized light. are doing. Accordingly, the incident light is separated into two polarization components (P-polarized light and S-polarized light) having different polarization directions, and the light source image formed by the first lens array (6) is a pair of light sources adjacent to each other having different polarization directions. It is formed as images (P image and S image). A half-wave plate (9) is provided on the light-emitting side of the PBS prism array (8) at a position where S-polarized light is incident. Since the S-polarized light and the P-polarized light form images at positions shifted from each other, it is possible to cause only the S-polarized light to enter the half-wave plate (9). One polarized light component (S-polarized light) is converted into a polarized light component (P-polarized light) having the same polarization direction as the other polarized light component (P-polarized light) by passing through the half-wave plate (9). About 90 ° rotation).

As described above, the polarization conversion optical system including the PBS prism array (8) and the half-wave plate (9) provides:
The illumination light is converted from random polarized light into linearly polarized light having a uniform polarization direction, and all the illumination light becomes P-polarized light. Since the polarization conversion optical system is configured in combination with the integrator optical system, illumination can be performed with almost no shift of the center axis of the illumination light having a strong energy distribution for both the P and S polarized illumination light. Therefore, it is efficient in illuminating the liquid crystal panel (13) with the microlens array (ML, FIG. 2), and uniform illumination light can be obtained by the integrator function.

The illumination light whose polarization direction is aligned by the polarization conversion optical system passes through the superimposing lens (10),
Three dichroic mirrors arranged at different angles
(11). The dichroic mirror (11)
(White light) is color-separated into each of the three primary colors RGB having an angle difference. Each of the RGB color lights generated by the color separation in the dichroic mirror (11) passes through a field lens (12) and illuminates a liquid crystal panel (13) as shown in FIG. The field lens (12) achieves telecentricity toward the liquid crystal panel (13).

The liquid crystal panel (13) has a rectangular display area, and RGB (in FIG. 2, R: broken line, G: solid line,
B: a two-dot chain line) is provided with a microlens array (ML) on the surface of the display area on the side where light of different colors enters at different angles. Then, the light after passing through the microlens array (ML) is modulated by the liquid crystal layer (LC). Since the polarizer (not shown) of the liquid crystal panel (13) is arranged in a direction transmitting the P-polarized light, there is almost no loss of light amount due to the polarizer, and
With respect to (13), illumination with high light use efficiency can be achieved.
Each lens cell of the micro lens array (ML) is a liquid crystal layer (LC)
Are arranged for each set of RGB pixel units, and RGB light beams enter each lens cell with an angle difference.
Therefore, the illumination light forms an image at a different position for each of the RGB color lights, and the pixels corresponding to each color are efficiently illuminated. Then, the projection lens (14) projects an image with the light modulated by the liquid crystal panel (13), and the display image of the liquid crystal panel (13) is projected on a screen (not shown).

In the color separation direction shown in FIG. 1B, the illumination light is angle-separated into each of RGB color lights, so that the numerical aperture (NA) of the entire illumination light is 3 for a single color (R, G, B). Double. For this reason, unless the NA of the light incident on the dichroic mirror (11) in the color separation direction is set to 1/3 or less of the direction in which color separation is not performed as shown in FIG. Color reproduction is reduced, and the tripled NA cannot be picked up by the projection lens (14) (for example, only 1/3 can be used), resulting in loss of light use efficiency and color unevenness. become. In order to solve this problem, in the present liquid crystal projector, the shape conversion optical system is configured to convert the light emitted from the light source (1) into parallel light with a different compression ratio depending on the direction. In other words, by compressing the luminous flux width of the parallel light emitted from the reflector (2a) in the horizontal direction (H) by the afocal system including the cylindrical lens system (4, 5a), in the display area of the liquid crystal panel (13). Horizontal direction corresponding to long side (α)
The compression ratio is different between (H) and the vertical direction (V) corresponding to the short side (β).

With the above configuration, the NA of the illumination light can be reduced to 1/3 without reducing the amount of light taken in from the light source (1). Therefore, it is possible to increase the light use efficiency while maintaining good color reproducibility, and obtain a bright and high-quality projected image. In addition, the direction (that is, the horizontal direction (H)) where the compression ratio is large, the long side (α) of the display area of the liquid crystal panel (13),
The direction of color separation by the dichroic mirror (11) is parallel to the same plane (for example, the paper surface).
The direction of separation (ie, vertical direction (V)) into two polarization components (P and S polarization) by the S prism array (8) is perpendicular to the plane.

FIG. 3 (A) shows a cross-hatched area of the light flux taking-in from the reflector (2a) in the present liquid crystal projector, and FIG. 3 (B) shows each lens of the second lens array (7) in the present liquid crystal projector. The positional relationship between a cell, a P image (IP) formed in the vicinity thereof, and a half-wave plate (9) is shown. FIG. 4 (A) shows, by cross-hatching, the range in which the luminous flux from the reflector (2a) is taken when the cylindrical lens system (4, 5a) is not used in the present liquid crystal projector, and FIG. In the case where the cylindrical lens system (4, 5a) is not used in the liquid crystal projector, the second
It shows a positional relationship between each lens cell of the lens array (7), a P image (IP) formed in the vicinity thereof, and a half-wave plate (9). P
Polarization separation direction by BS prism array (8) is vertical direction
(V), the S image (not shown) is in the region of the half-wave plate (9).
(Shaded area).

As can be seen by comparing the shapes of the P images (IP) shown in FIGS. 3B and 4B, the light source image formed near the second lens array (7) in the present liquid crystal projector is horizontal. It becomes longer in the direction (H). This is achieved by a cylindrical lens system (4, 5a) that compresses the luminous flux width only in the horizontal direction (H).
This is because the difference in the compression ratio at (H, V) appears as a magnification difference according to the ratio (that is, the compression ratio). In other words, the length of the light source image in the luminous flux compression direction is determined by the cylindrical lens system (4, 5a).
Is determined according to the afocal magnification of.

Here, if the aspect ratio of the liquid crystal panel (13) is 4: 3, the aspect ratio of the first and second lens arrays (6, 7) is also approximately 4: 3. Two light source images are formed for one lens cell in the vicinity of the second lens array (7).
In the horizontal direction (H) corresponding to (α), the aspect ratio of the area effective for one light source image is 2: 3. FIG.
As shown in (B), if the polarization separation direction is the vertical direction (V) corresponding to the short side (β) direction of the liquid crystal panel (13), the aspect ratio of the area effective for one light source image is 8: It becomes 3. The size of the light source image depends on the direction in which the luminous flux is compressed {that is, the horizontal direction.
(H)}, which is about three times larger, so the vertical direction (V)
In the case where is set as the polarization separation direction, the shape of the light source image and the shape of the effective light beam area near the second lens array (7) are better matched, and therefore, efficient illumination is possible. In the case of the present liquid crystal projector, when the light beam compression ratio is 8: 3, the shape of the light source image and the shape of the light beam effective area near the second lens array (7) are best matched.

The aspect ratio of the liquid crystal panel (13) is 1
In the case of 6: 9, the polarization separation direction is set to the short side of the liquid crystal panel (13).
In the vertical direction (V) corresponding to the (β) direction, the aspect ratio of the area effective for one light source image is 32: 9, and when the compression ratio is 32: 9, the shape of the light source image and the second lens array
(7) Matching with the shape of the effective light area in the vicinity is the best. From this viewpoint, when the aspect ratio of the display area of the liquid crystal panel (13) is α: β (where α> β), it is desirable that the ratio of the parallel light compression ratio is 2α / β: 1.
By setting such a compression ratio, the matching between the shape of the light source image and the shape of the effective light area near the second lens array (7) is improved, and efficient illumination can be performed.

FIG. 5 is a sectional view showing another embodiment of the liquid crystal projector according to the present invention. FIG. 5B shows a cross section of the entire liquid crystal projector viewed from the long side (α) side of the liquid crystal panel (13) (that is, from the direction parallel to the short side (β)). On the other hand, FIG. 5A shows a state in which the substantially L-shaped optical path shown in FIG. 5B is developed in one direction. That is, FIG. 5A shows a section from the light source (1) to the dichroic mirror (11) as viewed in a direction perpendicular to the display surface of the liquid crystal panel (13).
(14) is shown in a cross section viewed from the short side (β) side of the liquid crystal panel (13) {that is, from the direction parallel to the long side (α)}.

This liquid crystal projector has a light source (1), a reflector (2b), a UV-IR cut filter in the order of the optical path.
(3), concave cylindrical lens (5b), first lens array
(6), birefringent diffractive optical element (15), second lens array (7),
1/2 wavelength plate (9), superposition lens (10), dichroic mirror (11), field lens (12), liquid crystal panel (1
3) and a projection lens (14). Of these,
Reflector (2b) and concave cylindrical lens (5b) are shape conversion optics, first and second lens arrays (6,7) and superimposing lens (10) are lens array type integrator optics, birefringent diffractive optical elements The (15) and the half-wave plate (9) constitute a polarization conversion optical system, and the dichroic mirror (11) constitutes a color separation optical system.

The first feature of this liquid crystal projector is that the reflector (2b) has the function of a convex cylindrical lens in the shape conversion optical system. Reflector (2b)
Is focused on the position of the light source (1) and has horizontal (H) and vertical
(V) has an anamorphic aspheric surface having a curvature different from that of (V) as a reflecting surface. The anamorphic aspherical shape is a parabola in the cross section shown in FIG. 5A and an elliptical shape in the cross section shown in FIG. 5B. The concave cylindrical lens (5b) has an anamorphic aspheric lens surface having different curvatures in the horizontal direction (H) and the vertical direction (V) in order to convert the light beam from the reflector (2b) into parallel light. are doing. The anamorphic aspheric shape is straight in the cross section shown in FIG. 5A and circular in the cross section shown in FIG. 5B. Further, the curvature of the circle becomes maximum on the optical axis, and gradually changes as the distance from the optical axis in the vertical direction (V) increases. By using an anamorphic aspheric surface in this way, a convex cylindrical lens is not required, so that the number of components can be reduced. Further, the above-described compression of the light beam width is effectively achieved.

A second feature of the liquid crystal projector is that a birefringent diffractive optical element (15) is used as a polarization splitting element. The birefringent diffractive optical element (15) includes an optically anisotropic layer (for example, liquid crystal) made of a birefringent material and an optically isotropic layer (for example, a glass substrate) adjacent to the optically anisotropic layer on the diffraction grating surface. )
And performs polarization separation by its birefringence and diffraction. For example, P-polarized light passes through the birefringent diffractive optical element 15 without being diffracted on the diffraction grating surface, and S-polarized light is deflected by diffraction on the diffraction grating surface. Then, due to the polarization separation, a shift in the direction perpendicular to the optical axis occurs at the imaging position (that is, the light source image position) between the P-polarized light and the S-polarized light, and only the S-polarized light passes through the half-wave plate (9). Become.

In the configuration in which the illumination light is compressed and then incident on the first lens array (6), the number of divisions in the compression direction tends to decrease. Need to be done. Therefore, the number of lens cells in the polarization separation direction becomes considerably large, and when the PBS prism array (8) is used as shown in FIG. 1, the number of PBS prisms constituting the same becomes large. Therefore, since the number of constituent parts increases, there is a concern about an increase in cost. As shown in FIG. 5, the birefringent diffractive optical element (1
If (5) is used, polarization separation can be performed without depending on the number of lens cells, and the birefringent diffractive optical element (1
Since 5) can be configured with a very small number of parts, low-cost polarization separation can be performed effectively. For example,
If liquid crystal, which is a birefringent material, is sealed between the glass substrate and the diffraction grating substrate, a low-cost birefringent diffractive optical element (15) can be constructed with a very small number of components.

The third characteristic of the present liquid crystal projector is that
The half-wave plate (9) provided on the light-emitting side of the second lens array (7) is made of an amorphous birefringent thin film instead of a polymer film. When the number of lens cells in the polarization separation direction increases, the number of half-wave plates also increases. Therefore, when the half-wave plate is formed of a polymer film, the number of steps for attaching the half-wave plate increases, resulting in high cost. In addition, since the lens cell size is small, the influence of an error in the attachment position is large. Since the amorphous birefringent thin film is formed by vapor deposition, the half-wave plate (9) made of the amorphous birefringent thin film can be formed at one time, and the error of the position where the half-wave plate (9) is formed is reduced. It is also effective in reducing the size.

[0032]

As described above, according to the present invention, since the shape conversion optical system is configured to convert the light emitted from the light source into parallel light with different compression ratios depending on the direction, good color reproducibility is obtained. It is possible to obtain a bright and high quality projected image by increasing the light use efficiency while maintaining the image quality.

[Brief description of the drawings]

FIG. 1 is an optical configuration diagram showing a cross section of an embodiment of a liquid crystal projector.

FIG. 2 is a cross-sectional view showing a main part structure of a liquid crystal panel and an optical path of each color light in the liquid crystal projector of FIG.

FIG. 3 is a diagram schematically showing a light flux capturing range from a light source and a light flux effective area near a second lens array in the liquid crystal projector of FIG.

FIG. 4 is a diagram schematically showing a light flux taking-in range from a light source and a light flux effective area near a second lens array when a cylindrical lens system is not used in the liquid crystal projector of FIG.

FIG. 5 is an optical configuration diagram showing a cross section of another embodiment of the liquid crystal projector.

[Explanation of symbols]

 1 ... light source 2a ... reflector 2b ... reflector 4 ... convex cylindrical lens 5a ... concave cylindrical lens 5b ... concave cylindrical lens 6 ... first lens array 7 ... second lens array 8 ... PBS prism array 9 ... 1/2 wavelength plate 10 ... Superposition lens 11… dichroic mirror 13… liquid crystal panel ML… micro lens array 14… projection lens 15… birefringence diffractive optical element

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03B 33/12 G09F 9/00 360K G09F 9/00 360 H04N 9/30 H04N 9/30 9/31 Z 9 / 31 G02F 1/1335 530 F-term (reference) 2H088 EA13 HA13 HA16 HA20 HA24 HA25 HA28 KA01 MA05 2H091 FA05Z FA10Z FA11Z FA17Z FA26Z FA29Z FA41Z FD07 LA15 LA20 MA07 5C060 BA04 BA08 BB01 BC01 HD02 HC05 HC01 HD01 HC02 JA17 JB06 5G435 AA00 AA04 BB12 BB17 GG01 GG04 GG08 GG12 GG16 GG23 LL15

Claims (5)

[Claims] 1. A light source that generates white natural light, a shape conversion optical system that converts light emitted from the light source into parallel light, and a lens array type integrator that equalizes the spatial energy distribution of the parallel light. An optical system, a color separation optical system that separates the light having the uniform energy distribution into a plurality of color lights having an angle difference, and a microlens array on a surface of a display area on which the respective color lights are incident. A liquid crystal panel that modulates light after passing through the microlens array;
A projection lens for projecting an image with light modulated by the liquid crystal panel, wherein the integrator optical system divides incident light with a plurality of lens cells to form a plurality of light source images. A first lens array to be formed, and a second lens cell having the same number of lens cells that conjugate each lens cell of the first lens array and the liquid crystal panel so as to form a pair with each lens cell of the first lens array.
Further, the incident light is formed into a pair of light sources having different polarization directions so that the light source images formed by the first lens array are formed as a pair of light source images adjacent to each other having different polarization directions.
A polarization separating element that separates the polarized light into two polarized light components, and a half-wave plate that converts one polarized light component into a polarized light component having the same polarization direction as the other polarized light component. A liquid crystal projector characterized in that light emitted from a liquid crystal is converted into parallel light with different compression ratios depending on directions. 2. A display area of the liquid crystal panel has a rectangular shape, and the compression ratio is different between a direction corresponding to a long side and a direction corresponding to a short side of the rectangle, and a direction having a large compression ratio; The long side of the display area of the liquid crystal panel and the direction of color separation by the color separation optical system are parallel to the same plane, and the direction of separation into two polarization components by the polarization separation element is the plane. 2. The liquid crystal projector according to claim 1, wherein the liquid crystal projector is perpendicular to the projector. 3. The aspect ratio of the display area is α: β.
(Where α> β), the ratio of the compression ratio of the parallel light is 2α
3. The liquid crystal projector according to claim 2, wherein / β: 1. 4. A reflector, wherein the shape conversion optical system has a paraboloid having a focus at the light source position as a reflection surface,
A convex cylindrical lens for converging parallel light from the reflector in only one direction, and a concave cylindrical lens for returning light flux converged in only one direction by the convex cylindrical lens back to parallel light. 4. The liquid crystal projector according to claim 1, 2 or 3. 5. A reflector having an anamorphic aspheric surface having a focal point at the light source position and having different curvatures in a horizontal direction and a vertical direction as a reflecting surface, and a light beam from the reflector being converted into parallel light. 4. The liquid crystal projector according to claim 1, further comprising a concave cylindrical lens having lens surfaces having different curvatures in a horizontal direction and a vertical direction.