JP2006343692A - Projection display apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projection display apparatus capable of projecting a high definition image by arranging an axial chromatic aberration lens. <P>SOLUTION: White light emitted from a light source 111 is uniformized by an integrator optical system 112, and also, transmitted through a color polarizer 113 to become P-polarized R light and G light, further, transmitted through a color polarizer 118 to become S-polarized G light and P-polarized R light. The R light and the G light are separately and optically modulated by a G-light reflection type spatial optical modulating element 161 and an R-light reflection type spatial optical modulating element 162 arranged while leaving unequal distances from the polarized light separation surface 131 of a polarized beam splitter 103, and the G light is emitted through the axial chromatic aberration lens 170 corresponding to the unequal distance. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a projection display device using a reflective spatial light modulator.

  The color projection display device decomposes R (red), G (green), and B (blue) color lights related to the three primary colors from white light and leads them to the corresponding spatial light modulation elements. Color light modulated according to the video signal is synthesized and projected to display a color video on the screen.

  A method using a reflective spatial light modulation element as a color projection display device is advantageous for high resolution, but tends to have a complicated optical configuration. That is, a projection display device to which a reflective spatial light modulator is applied needs a polarization beam splitter to separate incident light that irradiates the spatial light modulator and reflected light modulated by the spatial light modulator. It is to do. In order to realize high contrast, it is usually necessary to operate two or more polarization beam splitters on one spatial light modulator, which complicates the optical configuration of the reflection type projection display device. . Various configurations have been proposed to solve this problem (see, for example, Patent Document 1).

JP 2001-174755 A

  By the way, as proposed in the above-mentioned Patent Document 1, in order to reduce the size of a color projection display device using a reflective spatial light modulation element, one polarized light among a plurality of polarizing beam splitters to be actuated is used. It is necessary to adopt a configuration in which two spatial light modulation elements are arranged with respect to the beam splitter.

  In the polarization beam splitter in which the two reflective spatial light modulation elements are arranged, two color lights corresponding to the respective color lights are incident with their polarization states being 90 degrees different from each other. Separated by the polarization separation plane. That is, the two color lights incident on the polarization beam splitter are separated depending on whether they are transmitted or reflected in accordance with the polarization state, and are incident on the reflective spatial light modulator.

  Considering general characteristics on the polarization separation surface of this polarization beam splitter, it is difficult to achieve total transmission, that is, transmission of 100%, and some reflection occurs. Attention is now focused on the color light that is incident on the corresponding reflective spatial light modulation element through the polarization separation surface of the polarization beam splitter, out of the two color light incident thereon. The colored light is transmitted through the polarization splitting surface and incident on the corresponding reflective spatial light modulator, and is modulated by the image signal corresponding to the colored light in the spatial light modulator, that is, the polarization state is changed and reflected. .

  The reflected modulated light is incident on the polarization separation surface again, but since the polarization state is changed, it is reflected by the polarization separation surface and emitted to the polarization beam splitter that combines the color lights, and is passed through the projection lens to the screen. Projected on top.

  Of the focused color light, the light reflected by the slight reflection described above is incident on a reflective spatial light modulation element corresponding to one color light different from the focused color light. The light reflected by the slight reflection is further reflected by this spatial light modulation element and is incident on the polarization separation surface again, but here the polarization state has not changed and the color light is synthesized through the polarization separation surface. Is output to a polarizing beam splitter and projected onto a screen via a projection lens.

  Usually, in a projection display device, in order to make the focal point of an image projected on a screen uniform with each color light, the distance from the screen to each reflective spatial light modulator is uniform, and the axis of the projection lens The upper chromatic aberration is set to be minimum for each color light. Therefore, the focused color light reflected by the reflective spatial light modulation element corresponding to the focused color light and the reflected reflected by the reflective spatial light modulation element corresponding to one color light different from the focused color light There was a problem that the colored light interfered with the projected screen to form interference fringes.

  The present invention has been made in view of the above points, and an object thereof is to provide a projection display device that can reduce interference fringes in a projected image and project a high-quality image.

In order to solve the above-mentioned problems, the present invention comprises means described in the following 1) to 2).
That is,
1) In a projection display device,
A light source that emits indefinitely polarized light;
First to third reflective spatial light modulators for optically modulating three primary color lights obtained by color-separating the indefinitely polarized light;
The indefinitely polarized light emitted from the light source is converted into a first color component light having a first polarization plane and a second polarization plane having a plane of polarization different from the first polarization plane by 90 degrees. A first wavelength-selective polarization conversion means for separating and emitting the second and third color component lights having a polarization plane of
A first polarization separation element that receives a light beam that has passed through the first wavelength-selective polarization conversion unit and branches an optical path between the first color component light and the second and third color component lights;
The second and third color component lights are incident from the first polarization separation element, and the polarization plane of the second color component light and the polarization plane of the third color component light are emitted so as to be orthogonal to each other. Second wavelength-selective polarization conversion means,
A polarization separation surface on which the second and third color component lights are incident from the second wavelength-selective polarization conversion means, and the polarization separation surface transmits the second color component light, and The light is incident on the second reflective spatial light modulator disposed at a first distance with respect to the polarization separation surface, and the third color component light is reflected so that the light is reflected on the polarization separation surface. A second polarization separation element that is incident on the third reflective spatial light modulation element installed at a second distance different from the first distance;
A polarization beam combining element that receives the modulated light modulated by the first to third reflective spatial light modulation elements and synthesizes and emits the modulated light; and
Between the second polarization separation element and the second reflective spatial light modulation element, or between the second polarization separation element and the third reflective spatial light modulation element, the first Means for generating axial chromatic aberration in accordance with a difference between a distance and the second distance;
A projection display device comprising:
2) The projection display device according to 1), wherein the means for generating the longitudinal chromatic aberration is a concave lens, a convex lens, or a flat plate.

According to the projection display device of the present invention, each reflective spatial light modulator configured to arrange two reflective spatial light modulators with respect to one polarization beam splitter, a screen, The reflection-type spatial light modulation elements are arranged so as to have different distances, and a means for generating chromatic aberration in which axial chromatic aberration is provided according to the difference in the distance is provided between the polarization beam splitter and any one of the reflection-type spaces. By disposing it between the light modulation elements, it is possible to provide a projection display device capable of reducing the interference fringes of the image projected on the screen and projecting a high-quality image. This is particularly effective for improving the image quality of dark images.
Further, in the case of a projection display device using a reflective spatial light modulation element, unnecessary reflected light generated by reflection of light emitted from the spatial light modulation element at an interface between an optical member and air or the like is again generated in the space. Concerning the ANSI contrast ratio, the unwanted reflected light is re-reflected by the spatial light modulation element when it returns to the light modulation element and is projected onto the screen, a concave lens or a convex lens is used as a means for generating the axial chromatic aberration. By using it, the exit pupil position and exit pupil diameter of the unnecessary reflected light deviate from the exit pupil position and exit pupil diameter of the projection imaging lens, so that there is an effect of improving the ANSI contrast ratio simultaneously with the reduction of the interference fringes.
Further, by using the configuration of the present invention, it is possible to design to simultaneously control the lateral chromatic aberration of the projection imaging lens.

  Hereinafter, the best mode for carrying out the invention of the projection display device according to the present invention will be described with reference to preferred embodiments.

FIG. 1 is a schematic plan view illustrating an optical configuration of a projection display device applied to the first embodiment.
A color separation / synthesis optical system 290 surrounded by a broken line includes first, second, and third polarization beam splitters 102, 103, and 104 that function as cubic or prismatic polarization separation elements, and a fourth that functions as a polarization composition element. The polarization beam splitter 105 is arranged so that its polarization separation surfaces 121, 131, 141, 151 as a whole are substantially X-shaped. Further, a color polarizer having a function of rotating the polarization planes of the R light and the G light by 90 degrees on the light transmitting surface (upper side surface of the first polarization beam splitter) on the incident side of the first polarization beam splitter 102. 113, a color polarizer 118 having a function of rotating the polarization plane of the G light by 90 ° is provided between the first and second polarization beam splitters 102 and 103. Further, a color polarizer 124 having a function of rotating the polarization plane of the R light by 90 ° is provided between the second and fourth polarizing beam splitters 103 and 105, and between the third and fourth polarizing beam splitters 104 and 105. Includes a color polarizer 115 having a function of rotating the polarization plane of the B light by 90 °.

The projection display device 300 applied to the first embodiment operates as follows.
Unfixed polarized white light emitted from the light source 111 enters the integrator optical system 112. Then, the white light is made uniform and aligned with the S-polarized light and enters the color polarizer 113. Since the color polarizer 113 is a wavelength-selective polarization conversion means that rotates the planes of polarization of the R light and the G light by 90 °, the S polarization associated with the R light and the G light transmitted through the color polarizer 113 is converted to P polarization. Converted. Further, since the color polarizer 113 has no effect on the B light, they remain S-polarized light.
Hereinafter, the transition of the optical path and the plane of polarization of each color light will be described individually.

  First, the P-polarized G light transmitted through the color polarizer 113 passes through the polarization separation surface 121 of the first polarization beam splitter 102 and enters the color polarizer 118. Since the color polarizer 118 is a wavelength-selective polarization conversion unit that rotates the polarization plane of the G light by 90 °, the P-polarized light related to the G light transmitted through the color polarizer 118 is converted into S-polarized light. The S-polarized G light transmitted through the color polarizer 118 is incident on the second polarization beam splitter 103, reflected by the polarization separation surface 131 of the second polarization beam splitter 103, and emitted from the light transmission surface 103a. The light passes through the chromatic aberration lens 170 and enters the reflective spatial light modulator 161 corresponding to G. Then, the reflection type spatial light modulation element 161 receives light modulation according to the video signal corresponding to G and reflects the light.

  The P-polarized component of the G light generated by the light modulation is transmitted again through the axial chromatic aberration lens 170, travels straight through the polarization separation surface 131 of the second polarization beam splitter 103, and enters the color polarizer 124. Since the color polarizer 124 is a wavelength-selective polarization conversion means that rotates the polarization plane of the R light by 90 °, it does not act on the G light and the P-polarized component of the G light goes straight through as it is P-polarized. Then, the light enters the fourth polarizing beam splitter 105. Then, the light travels straight through the polarization separation surface 151 of the fourth polarization beam splitter 105 and exits from the light transmission surface 105 c of the fourth polarization beam splitter 105.

  Next, the R light will be described. The P-polarized R light transmitted through the color polarizer 113 travels straight through the polarization separation surface 121 of the first polarization beam splitter 102 and enters the color polarizer 118. Since the color polarizer 118 is a wavelength-selective polarization conversion unit that rotates the polarization plane of the G light by 90 °, the color polarizer 118 does not act on the R light, and the R light remains P-polarized and the second polarizing beam splitter 103. Is incident on. The P-polarized R light incident on the second polarization beam splitter 103 travels straight through the polarization separation surface 131 of the second polarization beam splitter 103 and exits from the light transmission surface 103b to be reflected in R-type spatial light. The light enters the modulation element 162. Then, the reflection type spatial light modulation element 162 receives the light modulation corresponding to the video signal corresponding to R and is reflected.

  The S-polarized component of the R light generated by the light modulation is reflected by the polarization separation surface 131 of the second polarization beam splitter 103 and enters the color polarizer 124. Since the color polarizer 124 is a wavelength-selective polarization conversion unit that rotates the polarization plane of the R light by 90 °, the S-polarized component of the R light is converted into P-polarized light and enters the fourth polarizing beam splitter 105. To do. Then, the light travels straight through the polarization separation surface 151 of the fourth polarization beam splitter 105 and exits from the light transmission surface 105 c of the fourth polarization beam splitter 105.

  Next, the B light will be described. Since the color polarizer 113 has no effect on the B light, the B light remains as S-polarized light. Therefore, the S-polarized B light transmitted through the color polarizing filter 16 is polarized by the first polarization beam splitter 102. The light is reflected by the separation surface 121 and enters the third polarization beam splitter 104.

  The S-polarized B light is reflected by the polarization separation surface 141 of the third polarization beam splitter 104, exits from the light transmitting surface 104 d, and enters the B-type reflective spatial light modulator 163. Then, the reflection type spatial light modulation element 162 receives light modulation according to the video signal corresponding to B and is reflected.

  The P-polarized component of the B light generated by the light modulation is transmitted through the polarization separation surface 141 of the third polarization beam splitter 104 and enters the color polarizer 115. As described above, the color polarizer 115 is a wavelength-selective polarization conversion unit that rotates the polarization plane of the B light by 90 °, so that the P-polarized component of the B light is converted into the S-polarized light, and the fourth polarizing beam splitter. 105 is incident. Then, the light is reflected by the polarization separation surface 151 of the fourth polarization beam splitter 105 and is emitted from the light transmission surface 105 c of the fourth polarization beam splitter 105.

  In this way, the R light, G light, and B light emitted from the translucent surface 105c of the fourth polarizing beam splitter 105 expands the color image on a screen (not shown) via the projection lens 130 arranged in the subsequent stage. indicate.

  Here, the generation of interference fringes, which is a problem in the conventional optical system, will be described with reference to FIG. This figure is an enlarged view of the arrangement of the second polarizing beam splitter 103, the reflective spatial light modulator 161 for G light, and the reflective spatial light modulator 162 for R light. Since this is a description of a conventional optical system, the longitudinal chromatic aberration lens 170 is not disposed. As described in the problem to be solved by the above-described invention, a configuration in which two reflective spatial light modulation elements are arranged with respect to one polarization beam splitter, and a polarization separation surface of the polarization beam splitter is provided. Since the interference light fringes are generated in the color light reflected and reflected by the polarization separation surface, the P-polarized light incident on the second polarization beam splitter 103 is transmitted. R light becomes a problem.

  For the sake of explanation, symbols R, Rmi, Rmo, Rsi, and Rso are attached to each R light in the figure. The R light incident on the second polarization beam splitter 103 is incident as P-polarized light R as described above. Then, the light travels straight through the polarization separation surface 131 of the second polarization beam splitter 103, becomes Rmi, exits from the light transmission surface 103b, and enters the R-compatible reflective spatial light modulator 162.

However, due to the general characteristics of the polarization separation surface of the polarization beam splitter, a part of the incident R light R is reflected by the polarization separation surface 131 and emitted from the light transmission surface 103a of the second polarization beam splitter 103, so that it corresponds to G. R-light Rsi is incident on the reflective spatial light modulator 161.
The R light Rsi is reflected by the reflective spatial light modulation element 161 corresponding to G and becomes R light Rso. Since the R light Rso is P-polarized light, it travels straight through the polarization separation surface 131 and enters the fourth polarization beam splitter 105. Then, the light travels straight through the polarization separation surface 151 of the fourth polarization beam splitter 105 and exits from the light transmission surface 105 c of the fourth polarization beam splitter 105.

  On the other hand, the R light Rmi that travels straight through the polarization separation surface 131 of the second polarization beam splitter 103, exits from the light transmission surface 103b, and enters the R-compatible reflective spatial light modulator 162 is reflected by the reflective spatial light modulation. The element 162 receives light modulation corresponding to the video signal corresponding to R and is reflected. The S polarization component Rmo of the R light generated by the light modulation is reflected by the polarization separation surface 131 of the second polarization beam splitter 103 and enters the color polarizer 124. In the color polarizer 124, the S-polarized component of the R light is converted into P-polarized light and enters the fourth polarizing beam splitter 105. Then, the light travels straight through the polarization separation surface 151 of the fourth polarization beam splitter 105 and exits from the light transmission surface 105 c of the fourth polarization beam splitter 105.

  These R light Rmi and R light Rmo emitted from the light transmitting surface 105c of the fourth polarizing beam splitter 105 interfere with each other on the screen via the projection lens 123 to form interference fringes. This interference fringe is a dark screen in which the level of the R light Rmo is small and the R light Rmo and the R light Rmi are at the same level, and between the polarization separation surface 131 and the G-compatible reflective spatial light modulator 161. When the distance Lg and the distance Lr between the polarization separation surface 131 and the R-compatible reflective spatial light modulation element 162 coincide with each other, the distance Lg becomes most noticeable.

  In general, a projection display device has a configuration in which the distance from the screen to each color reflection type spatial light modulation element is made uniform in order to make the focus of the image projected on the screen uniform with each color light. That is, the distance Lg between the polarization separation surface 131 and the G-compatible reflective spatial light modulator 161 and the distance Lr between the polarization separation surface 131 and the R-compatible reflective spatial light modulator 162 are made to coincide with each other. Yes.

  Therefore, the axial chromatic aberration lens 170 applied to improve this arrangement relationship will be described. The distance Lg between the polarization separation surface 131 and the reflective spatial light modulation element 161 corresponding to G and the distance Lr between the polarization separation surface 131 and the reflective spatial light modulation element 162 corresponding to R are different from each other in the G correspondence. A reflective spatial light modulation element 161 and an R-compatible reflective spatial light modulation element 162 are provided.

  However, the distance Lg between the polarization separation surface 131 and the G-compatible reflective spatial light modulator 161 and the distance Lr between the polarization separation surface 131 and the R-compatible reflective spatial light modulator 162 are different from each other at positions G. When the corresponding reflective spatial light modulator 161 and the R reflective spatial light modulator 162 are installed, the focus on the screen is naturally shifted between the R light and the G light.

  Therefore, each of the G-corresponding G positions is located at a position where the distance Lg between the polarization separation surface 131 and the G-compatible reflective spatial light modulator 161 is larger than the distance Lr between the polarization separation surface 131 and the R-compatible reflective spatial light modulator 162. A reflective spatial light modulator 161 and an R-compatible reflective spatial light modulator 162 are installed, and an axial chromatic aberration lens 170 that is a concave lens is placed between the polarization separation surface 131 and the G-compatible reflective spatial light modulator 161. By arranging them, axial chromatic aberration is given so that a difference can be made between the focus position in the G region and the focus position in the R region.

  That is, an axis corresponding to the difference between the distance Lr between the polarization separation surface 131 and the R-compatible reflective spatial light modulator 162 and the distance Lg between the polarization separation surface 131 and the G-compatible reflective spatial light modulator 161. Upper chromatic aberration is applied to the axial chromatic aberration lens 170. 3A shows an example of spherical aberration, and FIG. 3B shows an example of astigmatism. The spherical aberration and astigmatism shown in FIGS. 4A and 4B indicate the amount of aberration generated on the incident side of the projection lens 130 when an image is projected onto the screen. The horizontal axis represents the magnitude of aberration, which is the amount of aberration, and the unit is μm. The vertical axis in the spherical aberration shown in FIG. 5A is the height of the light ray incident on the projection lens 130, and the distance from the optical axis (distance from the center) of the projection lens 130 is normalized to 1 as the maximum value. It expresses. The vertical axis in astigmatism shown in FIG. 4B is from the lens optical axis (distance from the center) of the projection lens 130 at the position of the reflective spatial light modulator disposed at the back focus position of the projection lens 130, respectively. The maximum value is normalized to 1 and expressed.

  The spherical aberration and astigmatism shown in FIGS. 4A and 4B are each 0 on the vertical axis and the value on the optical axis of the projection lens 130 is the axial chromatic aberration. The difference between the aberration in the green region and the aberration in the red region between the colors means that the back focus position is different, and this difference in aberration is the difference between the back focus position in the green region and the back focus in the red region. This corresponds to the difference in distance from the position. From the figure, it can be seen that the axial chromatic aberration in the green region is large and there is a difference of about 67 μm between the focus position in the red region and the focus position in the red region. Accordingly, the difference between the distance Lr between the polarization separation surface 131 and the R-compatible reflective spatial light modulator 162 and the distance Lg between the polarization separation surface 131 and the G-compatible reflective spatial light modulator 161 is also an optical distance. About 67 μm.

  In the figure, G indicates the aberration of the light wavelength of 0.54607 μm, and R indicates the aberration of the light wavelength of 0.630 μm. Astigmatism S indicates a sagittal ray, T indicates an aberration of a tangential ray, SR indicates an aberration of a sagittal ray of R light, SG indicates an aberration of a sagittal ray of G light, and TR indicates an aberration of a tangential ray of R light. Aberration, TG, indicates the aberration of tangential rays of G light.

The difference between the distance Lr between the polarization separation surface 131 and the R-compatible reflective spatial light modulator 162 and the distance Lg between the polarization separation surface 131 and the G-compatible reflective spatial light modulator 161 is the projection. This corresponds to the difference in optical distance between the back focus distance of each of the lenses 130 corresponding to the reflective spatial light modulator 162 corresponding to R and the back focus distance of the reflective spatial light modulator 161 corresponding to G.
This is because, when the image is in focus on the screen, the reflective spatial light modulator corresponding to each color is at the position of the back focus distance of the projection lens 130.

  As described above, in the projection display device using the reflective spatial light modulator, each reflective spatial light modulator configured to arrange two reflective spatial light modulators with respect to one polarization beam splitter. A reflective spatial light modulation element is arranged so that the distance between the spatial light modulation element and the screen is different, and an axial chromatic aberration lens is provided with axial chromatic aberration according to the difference in the distance. The interference fringes of the colored light incident in the P-polarized state, reflected and emitted in the S-polarized state are less noticeable, and the image quality of a dark image can be remarkably improved.

  In the above description, an example in which the axial chromatic aberration lens is a concave lens is shown, but a convex lens or a flat plate to which similar axial chromatic aberration is imparted may be arranged.

  In the above description, the axial chromatic aberration lens is provided. However, the reflective spatial light of the polarization beam splitter disposed between the projection lens and the reflective spatial light modulator corresponding to the color light in which the interference fringes are generated. On-surface chromatic aberration may be provided by giving a desired radius of curvature to the surface facing the modulation element, or a wave plate arranged for other purposes between the reflective spatial light modulation element and the polarization beam splitter, etc. A longitudinal chromatic aberration may be provided by giving a radius of curvature to the optical member, or a configuration in which a plurality of means are added to obtain a desired longitudinal chromatic aberration may be adopted.

  Furthermore, since the configuration of the optical system according to the first embodiment can be realized by adding an axial chromatic aberration lens to the same configuration as the conventional example, it is not necessary to significantly change the structure and adjustment method of the optical system. It is possible to realize a projection display device that can project a high-quality image.

Interference between the reflected light of the axial chromatic aberration lens 170 used in the configuration of Embodiment 1 and the light emitted from the R-type reflective spatial light modulator 162 may be a problem. FIG. 4 is a graph showing the anti-reflection coating characteristics applied to Example 2. In the second embodiment, interference due to the reflection of the axial chromatic aberration lens 170 can be suppressed by providing the axial chromatic aberration lens 170 with the anti-reflection coating characteristic that minimizes the reflection near the wavelength of 600 nm.
Specifically, the average regular reflectance in the wavelength band 430 nm to 500 nm is suppressed to 0.7% or less, the average regular reflectance in the wavelength band 500 nm to 680 nm is suppressed to 0.5% or less, and the wavelength bands 520 nm to 550 nm and 620 nm. It is desirable to keep the maximum regular reflectance at 650 nm to 650 nm to 0.3% or less and the maximum regular reflectance at the wavelength band 550 nm to 620 nm to 0.2% or less.

In the description of each of the above-described embodiments, the interference fringes of red light have been described based on the color arrangement of the optical system of the configuration example. However, in the projection display device using the reflective spatial light modulation element, one polarization beam splitter is used. This is a problem that can occur with colored light that is configured by arranging two reflective spatial light modulators, enters the polarization beam splitter in the P-polarized state, is reflected in the S-polarized state, and is emitted. You may comprise so that the interference fringe of blue light or green light may be reduced.
In the description of each of the above-described embodiments, the two color light beams of the white light emitted from the light source are applied to the polarization beam splitter in which two reflective spatial light modulation elements are arranged. The polarizing beam splitter arranged in the previous stage is configured to pass through and pass through, but it may be configured to be reflected by the polarizing beam splitter arranged in the previous stage.
The present invention is not limited to the embodiments described above.

1 is a schematic configuration diagram of an optical system of a projection display device applied to Example 1. FIG. It is a block diagram for demonstrating in detail the optical system used as the problem in the projection display apparatus applied to Example 1. FIG. 2 shows an example of chromatic aberration of an axial chromatic aberration lens applied to Example 1. FIG. It is the figure which showed the antireflection coating characteristic applied to Example 2.

Explanation of symbols

111 ... Light source 112 ... Integrator optical systems 113, 115, 118, 124 ... Color polarizers 102, 103, 104, 105 ... Polarizing beam splitters 121, 131, 141, 151 ... Polarization separating surfaces 123, 130 ... Projection lenses 161, 162 , 163 ... reflective spatial light modulator 170 ... axial chromatic aberration lens

Claims (2)

In the projection display device,
A light source that emits indefinitely polarized light;
First to third reflective spatial light modulators for optically modulating three primary color lights obtained by color-separating the indefinitely polarized light;
The indefinitely polarized light emitted from the light source is converted into a first color component light having a first polarization plane and a second polarization plane having a plane of polarization different from the first polarization plane by 90 degrees. A first wavelength-selective polarization conversion means for separating and emitting the second and third color component lights having a polarization plane of
A first polarization separation element that receives a light beam that has passed through the first wavelength-selective polarization conversion unit and branches an optical path between the first color component light and the second and third color component lights;
The second and third color component lights are incident from the first polarization separation element, and the polarization plane of the second color component light and the polarization plane of the third color component light are emitted so as to be orthogonal to each other. Second wavelength-selective polarization conversion means,
A polarization separation surface on which the second and third color component lights are incident from the second wavelength-selective polarization conversion means, and the polarization separation surface transmits the second color component light, and The light is incident on the second reflective spatial light modulator disposed at a first distance with respect to the polarization separation surface, and the third color component light is reflected so that the light is reflected on the polarization separation surface. A second polarization separation element that is incident on the third reflective spatial light modulation element installed at a second distance different from the first distance;
A polarization beam combining element that receives the modulated light modulated by the first to third reflective spatial light modulation elements and synthesizes and emits the modulated light; and
Between the second polarization separation element and the second reflective spatial light modulation element, or between the second polarization separation element and the third reflective spatial light modulation element, the first Means for generating axial chromatic aberration in accordance with a difference between a distance and the second distance;
A projection display device comprising: 2. The projection display device according to claim 1, wherein the means for generating the longitudinal chromatic aberration is a concave lens, a convex lens, or a flat plate.

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