JPH1054958A - Polarization generating device, display device and projection display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a small-sized polarization generating device capable of obtaining polarizing luminous flux with high light availability and high uniformity. SOLUTION: The polarization generating device 20 is provided with a first optical element 200 converging incident luminous flux and forming plural spatially separated intermediate luminous flux 202 and a second optical element 300 arranged in the vicinity of the position where the intermediate luminous flux 202 are converged. The first optical element 200 is composed of a luminous flux division lens 201 being an eccentric lens, and since the luminous flux division lenses adjacent in the Y direction are arranged in the state that respective lenses are shifted from each other in the X direction by a distance equivalent to a nearly half length of an arrangement pitch in the X direction, emitting luminous flux with remarkably uniform light intensity distribution and angular distribution and uniform polarization direction are converted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for generating, from an incident light beam having a random polarization state, an output light beam whose light intensity distribution in an illumination area is more uniform than the light intensity distribution of the incident light beam and whose polarization directions are almost uniform. The present invention relates to a polarization generator for causing the polarization to occur. Furthermore, the present invention relates to a display device and a projection display device using the above-mentioned polarization generator.

[0002]

2. Description of the Related Art For an illumination optical system of a display device using a panel of a type that modulates a polarized light beam, such as a liquid crystal panel, (1) the light intensity of the polarized light beam is high, and (2) the illumination area. It is mainly required that the light intensity distribution is uniform.

[0003] 1. Technology for increasing the light intensity of polarized light flux An optical system has been proposed that converts a random polarized light flux emitted from a light source into one kind of polarized light flux, thereby increasing the light use efficiency in a liquid crystal panel to achieve a bright display state. I have.

As one example, Japanese Patent Application Laid-Open No. 7-294906 describes
An outline of an optical system (referred to as a polarization optical system for convenience) disclosed in Japanese Patent Application Laid-Open Publication No. H10-209,655 will be described with reference to FIG. This optical system mainly includes a lens plate 910, a plurality of polarization beam splitters 920, a plurality of reflection prisms 930, and a λ / 2 phase difference plate 940. The principle is that an incident light beam, which is a random polarized light beam, is converted into two types of polarized light beams (a P-polarized light beam and an S-polarized light beam) by a polarizing beam splitter 920 having a polarized light beam separating surface 331 and a reflecting prism 930 having a reflecting surface 332. Then, the polarization direction of one polarized light beam after the separation is matched with the polarization direction of the other polarized light beam using a λ / 2 phase difference plate 940 to obtain one kind of polarized light beam, and the liquid crystal panel 950 is obtained by the light beam. Is to try to illuminate. However, in the process of separating polarized light beams, a space for forming two polarized light beams is required, and therefore, generally, it is unavoidable to widen the optical system. Therefore, in this polarization optical system, an incident light beam is condensed in advance by a lens plate 910, converted into a plurality of spatially separated intermediate light beams, and a reflection prism is formed in a space generated by converging the intermediate light beam. By disposing the 930 (reflection surface), one kind of polarized light beam is obtained without causing the optical system to widen.

[0005] 2. 2. Description of the Related Art As an illumination optical system that generates an illumination light flux such that the light intensity distribution in the illumination area is more uniform than the light intensity distribution of the incident light flux, for example, Japanese Patent Laid-Open No. 3-111806 Has been put to practical use.
Here, the disclosed integrator optical system is in principle the same as that used in the exposure apparatus.

The integrator optical system disclosed in the above publication uses first and second lens plates as two optical elements, and divides a light beam from a light source into a plurality of light beams constituting the first lens plate. The lens is split into intermediate light beams by a lens, and the intermediate light beams are superimposed and coupled via a second lens plate including a plurality of condenser lenses arranged near a position where the intermediate light beams converge, thereby illuminating one illumination area. Is what you do.

[0007]

SUMMARY OF THE INVENTION Japanese Patent Application Laid-Open No. 7-29490
In the polarization optical system disclosed in Japanese Patent Application Laid-Open No. 6-205, some problems arise because a random polarized light beam from a light source is simply converted into one type of polarized light beam.

First, since the intensity distribution of the light beam emitted from the light source is directly reflected on the illuminance distribution (intensity distribution) of the illumination light, it is difficult to obtain illumination light with uniform brightness and without color unevenness. It is. This is because the luminous flux emitted from the light source usually has remarkable brightness unevenness and color unevenness.

Second, based on the optical characteristics of the polarizing beam splitter and the reflecting prism, the P-polarized light beam emitted through the polarizing beam splitter and the S-polarized light beam emitted through the polarizing beam splitter and the reflecting prism. The light intensity and its spectral characteristics are different between. The same occurs between a polarized light beam that passes through a λ / 2 retardation plate used to align the polarization directions of two separated polarized light beams and a polarized light beam that does not pass. In this polarization optical system, since the light beams after aligning the polarization directions are not superimposed and coupled, unevenness in brightness and color is generated on the illumination area for the above-described reason, and a satisfactory illumination state cannot be obtained. . As means for preventing the brightness unevenness, a configuration using a light diffusing plate in the above-mentioned polarizing optical system has been proposed.However, since the light reaching the liquid crystal panel is obviously reduced by using the light diffusing plate, Contrary to the original purpose of the polarizing optical system to increase brightness, it cannot be a fundamental solution.

Third, the light emitted from the polarizing beam splitter 920 and the reflecting prism 930 is not condensed at all and reaches the liquid crystal panel while diverging with a large angle, so that the illumination efficiency is low and the display state is bright. Not only cannot be obtained, but also large color unevenness occurs depending on the direction in which the liquid crystal panel is viewed.

On the other hand, in the case of using the integrator optical system disclosed in Japanese Patent Application Laid-Open No. 3-111806, although the light intensity distribution can be made uniform to some extent, a random polarized light beam is still used as illumination light, so There is almost no effect on the improvement of the quality.

Further, in a projection type display device using a cross dichroic prism as a color light combining means, a bright projected image can be easily obtained without using a large-diameter and expensive projection lens. Depending on the light characteristics of the light source used, dark shadows are likely to occur in the projected image due to light scattering generated at the junction of the four right-angle prisms constituting the cross dichroic prism. This dark shadow can be made inconspicuous by making the intensity distribution and the angular distribution of the illumination light illuminating the modulation means uniform. However, in the conventional illumination system, the uniformity of the light intensity distribution and its angular distribution was not sufficient, so that the presence of the dark shadow could not be made inconspicuous.

Accordingly, there has not been an optical system for uniformly and efficiently illuminating a specific illumination area with one kind of polarized light beam.

In view of the above, the object of the present invention is to
First, a polarization generator for generating one type of polarized light beam from an incident light beam that is a random polarized light beam, in which the light intensity distribution in the illumination area is more uniform than that of the incident light beam and the polarization direction is almost uniform. The second is to realize
Using such a polarization generator, a display device that is bright and free from brightness unevenness and color unevenness is realized.
In addition, by using such a polarization generator, it is possible to obtain a projected image that is bright and free from uneven brightness and color, without using an expensive projection lens having a small F-number and a large aperture. It is an object of the present invention to provide a projection display device that can display a projected image in which dark shadows generated by a cross dichroic prism are not noticeable even when a prism is used as a color light combining unit. The F number is the ratio between the focal length and the lens diameter.

[0015]

[Means for Solving the Problems]

1. Polarized Light Generator (1) The polarized light generator of the present invention condenses an incident light beam and converts it into a plurality of intermediate light beams spatially separated from each other.
And a second optical element arranged near a position where the intermediate light beam converges, wherein the first optical element comprises a plurality of light beam splitting lenses arranged in a matrix, Each of the plurality of light beam splitting lenses is an eccentric lens, and the light beam splitting lenses adjacent to each other in the column direction are arranged in a state shifted from each other in the row direction, and the second optical element converts each of the intermediate light beams. Polarized light beam separating means for spatially separating the S polarized light beam and the P polarized light beam; and the P polarized light beam separated by the polarized light beam separating means, and the polarization direction of one of the S polarized light beams to the other. Polarization conversion means for converting the polarization direction, the other polarized light flux, and the superimposing coupling means for superimposing and coupling the one polarized light flux whose polarization direction has been converted by the polarization conversion means to output light flux, Characterized in that it has.

Here, the plurality of light beam splitting lenses constituting the first optical element are arranged such that light beam splitting lenses adjacent in the column direction are separated from each other in the row direction by a distance corresponding to substantially half the length of the array pitch in the row direction. Are arranged in a shifted state. By adopting such an arrangement mode, the brightness can be reduced even when the incident light beam has a locally larger light intensity distribution in the cross section of the light beam as compared with the case where the light beam splitting lens is not staggered. A uniform, high-quality polarized light beam without color unevenness can be obtained as illumination light. In particular, when the light intensity distribution of the light beam is not completely disordered, as seen in the light beam emitted from the light source including the light source lamp and the reflector, and when the light intensity distribution has certain characteristics and tendencies, By using the above first optical element, the light intensity distribution and its angular distribution in the illumination area can be made extremely uniform.

For example, a light beam emitted from a light source provided with a parabolic reflector has a light intensity distribution with the optical axis of the light source as a symmetric axis (the light intensity is large near the optical axis and small at the periphery).
And its angular distribution (the emission angle is wide near the optical axis and narrow at the periphery). Therefore, in order to obtain illumination light having a uniform light intensity distribution from such a light beam, (a) increase the number of light beam splitting lenses, that is, increase the number of intermediate light beams generated by the light beam splitting lens, or , (B) a method of arranging the beam splitting lens irregularly with respect to various characteristics of the light beam such as the light intensity distribution and its angle distribution can be considered.
In the method (a), the interface between the light beam splitting lenses increases with the increase of the light beam splitting lens, and the light loss at the interface increases. Therefore, the light intensity distribution in the illumination area can be made uniform, but the brightness is reduced. On the other hand, in the method (b), it is difficult to arrange the light beam splitting lens without any gap and completely irregularly.

On the other hand, the first optical element of the polarized light generator of the present invention is capable of simply connecting adjacent light beam splitting lenses in the column direction to each other without generating an unnecessary gap between the light beam splitting lenses. Only by adopting the displaced arrangement, it is possible to mutually cancel or weaken certain characteristics and tendencies in the light intensity distribution, and to make the light intensity distribution and its angular distribution in the illumination area extremely uniform. Accordingly, it is not necessary to increase the number of light beam splitting lenses more than necessary, and it is possible to reduce light loss at the interface of the light beam splitting lenses, and to obtain illumination light having a uniform light intensity distribution and its angle distribution without lowering brightness. Can be.

Here, the shift amount of the light beam splitting lens adjacent in the column direction is not particularly limited. However, in consideration of the effect of the shift amount of the light beam splitting lens on the light intensity distribution of the illumination light and its angular distribution, and the ease of arrangement of the second optical element arranged corresponding to the light beam splitting lens, the shift amount is considered. Is optimally set to a distance corresponding to almost half the length of the array pitch in the row direction.

Next, since the second optical element of the polarization generator of the present invention finally superimposes and couples the intermediate light beam on one illumination area, the incident light beam has a large light intensity in the cross section of the light beam. Even if it has a distribution, a polarized light beam having uniform brightness and no color unevenness can be obtained as illumination light. In the integrator optical system introduced earlier, the intermediate light flux is finally superimposed and coupled on one illumination area, so that the light intensity distribution on the illumination area can be made uniform to some extent. Since there is a process of spatially separating the intermediate light beam into a P-polarized light beam and an S-polarized light beam, the number of light beams superimposed and coupled on the illumination area is determined by the integrator optics (when the number of light beam splitting lenses is the same). The intensity is twice as large as that of the system, and as a result, there is an excellent feature that the light intensity distribution on the illumination area can be remarkably uniformed as compared with the integrator optical system. In the process of spatially separating the intermediate light beam into a P-polarized light beam and an S-polarized light beam, and in the process of converting the polarization direction of one polarized light beam to the polarization direction of the other polarized light beam, light absorption and light scattering are performed. , It is possible to obtain a light beam with a substantially uniform polarization direction with very high efficiency.

Furthermore, when the intermediate light beam cannot be separated into a P-polarized light beam and an S-polarized light beam with uniform light intensity and spectral characteristics, or when the polarization directions of both polarized light beams are aligned, the light intensity of one polarized light beam and its spectral characteristics are obtained. Is changed, it is possible to obtain a polarized light beam having uniform brightness and no color unevenness as illumination light.

The polarization converting means has a function of converting one of the two types of polarized light beams separated by the polarized light beam separating means into the other polarization direction.
The function of rotating the polarization direction to any of the polarized light beams may be used to finally align the polarization directions of the two polarized light beams to one type.

Here, the polarization generator of the present invention has the above-mentioned second configuration.
The optical element constituting the optical element is a compact optical element in which a plurality of polarized light beam separating means are arranged in one direction and integrated, and the second optical element can be reduced in size.

As described above, according to the above-described configuration of the polarization generator of the present invention, all the problems described above can be solved, and the light intensity distribution in the illumination region and the light intensity distribution in the illumination area can be obtained from the random polarized light beam. The angle distribution is more uniform than that of the incident light beam, and the output light beam with almost uniform polarization direction can be generated with very high efficiency.

(2) In the above-mentioned polarized light generating apparatus of the present invention, the polarized light beam separating means includes a reflecting surface and a polarized light beam separating surface, and the reflecting surface and the polarized light beam separating surface are arranged in parallel with each other. You may take.

Using a polarized light beam separating means having a pair of reflecting surfaces and a polarized light beam separating surface, the intermediate light beam is converted into the P-polarized light beam and the S-polarized light beam.
In order to spatially separate the light into the polarized light, a new space in which the S-polarized light can exist is required. When the light beam enters the polarized light beam separating means without changing the light beam diameter of the intermediate light beam at all,
The width of the luminous flux after the polarization luminous flux separation (the total width of the width of the P-polarized luminous flux and the width of the S-polarized luminous flux) is twice as large as the width of the incident luminous flux, which means that the optical system becomes larger (Widening)
Leads to.

The structure of the above-mentioned polarized light generating apparatus according to the present invention is such that a plurality of intermediate light beams are formed by condensing an incident light beam while splitting it by a light beam splitting lens, and a polarized light beam is provided near a position where each intermediate light beam converges. The separating means forms a plurality of pairs of spaces each including a space in which the intermediate light beam exists and a space adjacent to the space and in which no light beam exists. In the polarization generator of the present invention, the space in which no light beam exists is used as a new space in which the S-polarized light beam can exist. With the above configuration, the P-polarized light beam and the S-polarized light beam can be completely spatially separated while the total width of the light beam after the polarized light beam separation is not larger than the width of the incident light beam before the polarized light beam separation. it can. Accordingly, in the process of generating an outgoing light beam having a substantially uniform polarization direction from an incident light beam, which is a random polarized light beam, the total width of the light beam does not increase, so that the optical system can be downsized. Further, the fact that the total width of the light beam does not expand means that the light beam does not have a large angle component at the stage of superimposing and combining a plurality of polarized light beams, and therefore, when illumination is performed using these light beams. , High illumination efficiency can be obtained. still,
For example, if a dielectric multilayer film is used, a reflecting surface or a polarized light beam separating surface with almost no light absorption or light scattering can be easily realized. Therefore, it is possible to generate a specific polarized light beam with very high efficiency.

Further, by arranging the reflection surface of the polarized light beam separating means and the polarized light beam separating surface in parallel with each other, the two kinds of polarized light beams spatially separated by the polarized light beam separating means can be kept parallel to each other. The polarized light beams can be emitted from the polarized light beam separating means, and thus these two types of polarized light beams can be finally easily overlapped and combined on one illumination area. still,
The installation angle of the polarized light beam separating surface and the reflecting surface is set to approximately 45 degrees with respect to the incident direction of the intermediate light beam. Further, since the reflection surface and the polarized light beam separating surface are arranged in parallel with each other, the blocks of the polarized light beam separating means can be collectively formed for each column. This can be facilitated and at the same time cost can be reduced.

(3) In the above-mentioned polarized light generating apparatus of the present invention, the external shape of the light beam splitting lens is rectangular, so that a plurality of light beam splitting lenses overlap a specific plane without any gap and overlap each other. Therefore, the light utilization efficiency when dividing the incident light beam into a plurality of intermediate light beams can be extremely increased. Further, when a display device or a projection display device is configured by using the polarization generating device of the present invention, the external shape of a modulation unit such as a liquid crystal panel which is an illuminated body is generally rectangular, so that a light beam splitting lens is used. The light utilization efficiency is better if the outer shape in the plane formed by the column direction and the row direction is also rectangular.

(4) In the above-mentioned polarized light generator of the present invention, the second optical element further includes a collector for condensing the plurality of intermediate light beams spatially separated by the first optical element. By having a light means and comprising the plurality of condensing lenses arranged in a matrix, the condensing means ensures that the intermediate light beam is incident on the polarized light beam separating means, that is, prevents waste of light from the light source. Thus, the light use efficiency can be improved. In particular, the size of the second optical element can be made smaller than the size of the first optical element without deteriorating the performance of the polarization generator by adopting the condensing means. Can be achieved. Further, by adopting the condensing means, the degree of freedom of arrangement and size of the polarized light beam separating means in the row direction can be increased. For example, with the central axis of the polarization generator as a symmetric axis, a plurality of polarization beam splitters are arranged so that the polarization beam splitters arranged in the row direction are symmetrically arranged, or, as described later, the polarization generator. In the vicinity of the central axis, a polarized light generator can be configured by using a polarized light beam separating means having a large dimension, and a polarized light beam separating means having a small dimension in the periphery thereof. As a result, the light use efficiency can be further improved. In addition, the size of the apparatus can be reduced. Note that, in general, the size in the row direction of the light beam splitting lens forming the first optical element is the same as the size in the row direction of the polarized light beam splitting means forming the second optical element. In many cases, the same lens body as the light beam splitting lens can be used as the condensing lens, so that the manufacturing cost of the light beam splitting lens and the light collecting lens can be reduced. There is.

(5) Further, in the above-mentioned polarized light generating apparatus of the present invention, by making all of the plurality of condensing lenses eccentric lenses, the incident angle of the intermediate light beam incident on the polarized light beam separating means can be adjusted. , The angle of incidence with respect to the polarized light beam separating surface is set to the most ideal angle (generally 45 °).
Degrees).

2. Display device and projection display device (6) The display device of the present invention is a light source unit, and a first optical device that condenses a light beam from the light source unit and converts the light beam into a plurality of spatially separated intermediate light beams. An element, a second optical element arranged near a position where the intermediate light beam converges,
A modulating means for modulating a light beam emitted from the optical element, wherein the first optical element comprises a plurality of light beam splitting lenses arranged in a matrix, and the plurality of light beam splitting lenses. Are eccentric lenses, and light beam splitting lenses adjacent in the column direction are arranged in a state of being shifted from each other in the row direction. The second optical element converts each of the intermediate light beams into an S-polarized light beam and a P-polarized light beam. A polarized light beam separating unit that spatially separates and emits the polarized light beam, and the polarization direction of any one of the P-polarized light beam and the S-polarized light beam emitted from the polarized light beam separating unit to the other polarization direction And the other polarized light flux, and the superimposing coupling means for superimposing and coupling the one polarized light flux whose polarization direction has been converted by the polarization converting means to convert it into an output light flux. Characterized in that it.

(8) A first projection type display apparatus according to the present invention is a light-emitting device, comprising: a light source unit; and a light source unit that collects light beams from the light source unit and converts the light beams into a plurality of intermediate light beams spatially separated from each other. A first optical element, a second optical element arranged near a position where the intermediate light beam converges, a modulating means for modulating a light beam emitted from the second optical element, and a light beam modulated by the modulating means. A projection optical unit for projecting a light beam, wherein the first optical element includes a plurality of light beam splitting lenses arranged in a matrix, and each of the plurality of light beam splitting lenses is decentered. Lens
Further, the light beam splitting lenses adjacent to each other in the column direction are arranged so as to be shifted from each other in the row direction, and the second optical element spatially separates each of the intermediate light beams into an S-polarized light beam and a P-polarized light beam. Polarized light beam separating means, the P-polarized light beam separated by the polarized light beam separating means, and the polarization converting means for converting one of the S-polarized light beams into the other polarization direction, and the other one. The present invention is characterized in that there is provided a superimposing / coupling unit that superimposes and couples the polarized light beam and the one polarized light beam whose polarization direction has been converted by the polarization conversion unit to convert the polarized light beam into an output light beam.

(13) Further, the second projection type display device of the present invention converges a light source unit and a light beam from the light source unit and converts it into a plurality of intermediate light beams spatially separated from each other. A first optical element, a second optical element disposed near a position where the intermediate light beam converges, and a color light separating unit that separates the light beam emitted from the second optical element into two or more color lights. Two or more modulating means provided corresponding to each color light emitted from the color light separating means, a color light synthesizing means for synthesizing the color lights modulated by the respective modulating means, and a color light synthesizing means. Projection optical means for projecting the combined light beam, wherein the first optical element comprises a plurality of light beam splitting lenses arranged in a matrix, and the plurality of light beam splitting lenses. These are also decentered lenses, and the light beam splitting lenses adjacent to each other in the column direction are arranged so as to be shifted from each other in the row direction. The second optical element converts each of the intermediate light beams into an S-polarized light beam and a P-polarized light. A polarized light beam separating unit that spatially separates the light beam into a polarized light beam, and a polarization direction of one of the P-polarized light beam and the S-polarized light beam emitted from the polarized light beam separating unit. And the other polarized light flux, and the superimposing coupling means for superimposing and coupling the one polarized light flux whose polarization direction has been converted by the polarization converting means to convert the polarized light flux into an output light flux. Features.

Here, the plurality of light beam splitting lenses constituting the first optical element are arranged such that light beam splitting lenses adjacent in the column direction are separated from each other in the row direction by a distance corresponding to substantially half the length of the array pitch in the row direction. Are arranged in a shifted state. As described above, such a configuration does not cause an unnecessary gap between the light beam splitting lenses, and merely adopts an arrangement in which light beam splitting lenses adjacent to each other in the column direction are shifted from each other. Certain characteristics and trends in the distribution can be mutually canceled out or weakened, and the light intensity distribution and its angular distribution in the illumination area can be made extremely uniform. Therefore, there is no need to increase the number of light beam splitting lenses more than necessary, and light loss at the interface of the light beam splitting lens can be reduced.
Illumination light having a uniform light intensity distribution and its angular distribution can be obtained without lowering the brightness. This effect is not particularly disordered in the light intensity distribution of the light beam, as seen in the light beam emitted from the light source including the light source lamp and the reflector, but has certain characteristics and tendencies in the light intensity distribution. This is remarkable in the case where the light intensity distribution and its angular distribution in the illumination area can be made extremely uniform.

The reason is as described above.

The shift amount of the light beam splitting lens adjacent in the column direction is not particularly limited. However, in consideration of the effect of the shift amount of the light beam splitting lens on the light intensity distribution of the illumination light and its angular distribution, and the ease of arrangement of the second optical element arranged corresponding to the light beam splitting lens, the shift amount is considered. Is optimally set to a distance corresponding to almost half the length of the array pitch in the row direction.

As described above, the second optical element once divides the incident light beam into a plurality of intermediate light beams, and further divides the plurality of intermediate light beams into twice as many polarized light beams (P-polarized light beams). After being split into a light beam and an S-polarized light beam, the polarized light beams are finally superimposed and coupled on one illumination area, so that even if the incident light beam has a large light intensity distribution in the cross section of the light beam. In addition, a polarized light beam having uniform brightness and no color unevenness can be obtained as illumination light. Furthermore, when the intermediate light beam cannot be separated into a P-polarized light beam and an S-polarized light beam with uniform light intensity and spectral characteristics, or when the polarization directions of both polarized light beams are aligned, the light intensity of one polarized light beam and its spectral characteristics change. Even in such a case, a polarized light beam having uniform brightness and no color unevenness can be obtained as illumination light.

Thus, the display device of the present invention, and
According to the above configuration of the first and second projection display devices, it is possible to obtain an extremely uniform image over the display surface and the entire projection surface.

The light source section generally includes a light source lamp and a reflector in many cases. Examples of the light source lamp include a metal halide lamp, a xenon lamp, and a halogen lamp, and examples of the reflector include a parabolic reflector and a reflector. Elliptical reflectors, spherical reflectors and the like can be used. In addition, a transmissive liquid crystal panel or a reflective liquid crystal panel can be used as the modulating means. In particular, in a reflective projection display device using a reflective liquid crystal panel,
Since illumination light having very little brightness unevenness and color unevenness is required, it is particularly effective to apply the polarization generator of the present invention when configuring such a projection display device.

(7) (9) (14) In the above display device of the present invention and the first and second projection display devices, the polarized light beam separating means comprises a reflecting surface and a polarized light beam separating surface. The reflective surface and the polarized light beam separating surface may be arranged in parallel with each other.

As described above, by adopting such a configuration, the P-polarized light beam is prevented while the total width of the light beam after the polarized light beam separation is not larger than the width of the incident light beam before the polarized light beam separation. And the S-polarized light beam can be completely spatially separated. Accordingly, in the process of generating an outgoing light beam having a substantially uniform polarization direction from an incident light beam, which is a random polarized light beam, the total width of the light beam does not increase, so that the optical system can be downsized. Thus, according to the present invention,
A display device that is very small and has excellent handling properties, and
A projection display device can be provided.

Further, the fact that the total width of the light beam does not expand means that the light beam does not have a large angle component at the stage of superimposing and combining a plurality of polarized light beams, and therefore, the illumination is performed using these light beams. In this case, high illumination efficiency can be obtained. In the process of generating polarized light, almost no light absorption is involved, so that a specific polarized light beam can be generated with very high efficiency. Therefore, according to the present invention, it is possible to provide a projection display device with a bright image without using an expensive projection lens having a small F number and a large aperture.

As described above, according to the display device of the present invention and the first and second projection display devices described above, a very small display device with excellent handleability and a projection display device are provided. It is possible to obtain a bright and uniform image over the entire projection surface. Further, since there is no necessity to use a large-diameter expensive projection lens having a small F-number, it is possible to provide a less expensive projection display device.

Further, by arranging the reflection surface of the polarized light beam separating means and the polarized light beam separating surface in parallel with each other, the two kinds of polarized light beams spatially separated by the polarized light beam separating means can be kept parallel to each other. The light is emitted from the polarized light beam separating means, and these two types of polarized light beams can be finally easily overlapped and combined on one illumination area. In addition, the installation angle of the polarized light beam separating surface and the reflecting surface is set to approximately 45 degrees with respect to the incident direction of the intermediate light beam. Further, since the reflection surface and the polarized light beam separating surface are arranged in parallel with each other, the blocks of the polarized light beam separating means can be collectively formed for each column. This can be facilitated and at the same time cost can be reduced.

(10) (15) Further, the second optical element is provided with a condensing means for condensing the intermediate light flux comprising a plurality of condensing lenses arranged in a matrix, so that the polarized light beam separation is performed. The intermediate light beam can be surely made incident on the means, and it is possible to further improve the light use efficiency of the display device and to reduce the size of the device itself. Note that, in general, the size in the row direction of the light beam splitting lens forming the first optical element is the same as the size in the row direction of the polarized light beam splitting means forming the second optical element. In many cases,
In this case, since the same lens body as the light beam splitting lens can be used as the light collecting lens, there is an effect that the manufacturing cost of the light beam splitting lens and the light collecting lens can be reduced.

(11) (16) Further, when all of the plurality of condenser lenses are eccentric lenses, the incident angle of the intermediate light beam entering the polarized light beam separating means can be adjusted, and the polarized light beam separation The angle of incidence on the surface can be set to the most ideal angle (generally 45 degrees). As a result, it is possible to further improve the light use efficiency and to realize a projection display device capable of obtaining a bright projection image.

(12) (17) Further, the condensed image formed by the light beam splitting lens located near the optical axis of the light source section is formed by the light beam splitting lens located at the peripheral portion away from the light source optical axis. Since the size is smaller than the condensed light image, the size of the polarized light beam separating means, which is located near the optical axis of the light source unit, of the plurality of polarized light beam separating means,
When the size is larger than the size of the polarized light beam separating means located in the peripheral portion away from the optical axis of the light source unit, the efficiency of the optical system can be further improved, and at the same time, the size of the polarized light beam separating means is optimized. Therefore, downsizing of the optical system can be achieved.

(18) In the second projection type display apparatus according to the present invention, the color light separating means for separating the light beam emitted from the second optical element into two or more color lights, and the respective color lights And two or more modulating means provided in correspondence with each other, and a color light synthesizing means for synthesizing the color lights modulated by the respective modulating means. , It is possible to arrange a dedicated modulating means for each of the two or more separated color lights, and as a result, it is bright and has good color expression, A small projection display device capable of displaying a high-resolution color image can be realized.

Here, a cross dichroic prism in which dichroic films are arranged in a cross shape can be used as the color light synthesizing means. When a cross dichroic prism is used, the distance between the projection optical means (projection lens) and the modulation means (liquid crystal panel) can be shortened, so that a large-diameter expensive F-number and an expensive projection lens can be used. Also, a bright projection image can be displayed. on the other hand,
Since light scattering occurs at the junction of the four right-angle prisms constituting the cross dichroic prism, a dark shadow may appear on a projected image in a projection display device using the cross dichroic prism as a color light combining unit.
However, this dark shadow can be made inconspicuous by making the intensity distribution and the angular distribution of the illumination light illuminating the modulation means uniform. Therefore, according to the projection display device of the present invention, since the light intensity distribution and its angular distribution in the illumination area can be made extremely uniform, the presence of dark shadows generated when using the cross dichroic prism can be made extremely inconspicuous, and as a result, High quality projected images can be obtained.

By integrating at least two or more of the condensing means, the polarized light beam separating means, the polarization converting means, and the superimposing and coupling means for constituting the second optical element, Light loss at the interface between the condensing means and the polarized light beam separating means, the interface between the polarized light beam separating means and the polarized light converting means, or the interface between the polarized light converting means and the superimposing coupling means can be reduced. Efficiency can be further improved.

[0052]

Embodiments of the present invention will be described below with reference to the drawings. In the following embodiments, three directions perpendicular to each other are referred to as X, Y, and Z directions for convenience unless otherwise specified. Also,
In any of the embodiments, the configuration is such that an S-polarized light beam is obtained as one type of polarized light beam from a random polarized light beam, but it is needless to say that a P-polarized light beam may be obtained.

(Polarized Lighting Apparatus 1) FIG. 1 shows an example of a polarized light illuminating apparatus 1 constituted by using the polarized light generating apparatus of the present invention. It is. FIG. 1 is a cross-sectional view on an XZ plane passing through the center of a second optical element 300 described in detail later. The polarized light illuminating device 1 of the present embodiment is generally constituted by a light source unit 10 and a polarized light generator 20 arranged along the system optical axis L. The random polarized light beam emitted from the light source unit 10 is converted by the polarization generator 20 into one type of polarized light beam having a substantially uniform polarization direction, and reaches the illumination area 90.

The light source section 10 is generally composed of a light source lamp 101 and a parabolic reflector 102. Light emitted from the light source lamp is reflected in one direction by the parabolic reflector 102, and is substantially parallel light flux. And enters the polarization generator 20. Here, the light source unit 10 is arranged such that the light source optical axis R of the light source unit 10 is shifted parallel to the system optical axis L by a certain distance D in the X direction.

Next, the polarization generator 20 is composed of a first optical element 200 and a second optical element 300.

The appearance of the first optical element 200 is shown in FIG.
As shown in FIG. 2, a plurality of light beam splitting lenses 201 having a rectangular outer shape on an XY plane are arranged in a matrix, and the light beam splitting lenses adjacent in the Y direction (column direction) Each of them is arranged so as to be shifted from each other in the X direction by a distance corresponding to substantially half the length of the arrangement pitch in the direction (row direction). Here, the light source unit 1
0 and the first optical element 200 are determined by the light source unit 10.
Is set so that the light source optical axis R is located at the center of the first optical element 200.

Each of the light beam splitting lenses 201 constituting the first optical element 200 is an eccentric lens, that is, in each light beam splitting lens, the lens optical axis is set at a position shifted from the center of the light beam splitting lens. Have been. Here, the setting state of the lens optical axis in each light beam splitting lens 201 is shown in FIG. FIG. 3 is a diagram showing the position of the lens optical axis in each of the light beam splitting lenses 201 when the first optical element 200 is viewed from the light source unit side. A position shifted in the −X direction from the center 205 (the amount of eccentricity in this case is の of the size of the light beam splitting lens in the X direction)
Further, in the light beam splitting lenses forming the even-numbered rows, the respective lens optical axes 204 are shifted from the lens center 205 in the + X direction (the amount of eccentricity is the same as that of the light beam splitting lenses forming the odd-numbered rows). Is set. That is, two types of eccentric lenses having different eccentric directions are alternately arranged in the row direction. Note that the eccentric direction and the eccentric amount of each light beam splitting lens are not fixed values because they change depending on the shape and size of a second optical element described later.

Returning to FIG. 2, the description will be continued. The light incident on the first optical element 200 is split into a plurality of intermediate light beams 202 by the light beam splitting lens 201, and at the same time, by the light condensing action of the light beam splitting lens, in a plane perpendicular to the system optical axis L (XY in FIG. 1). The same number of condensed images 203 as the number of light beam splitting lenses are formed at the position where the intermediate light beam (on the plane) converges. Since the light beam splitting lens 201 constituting the first optical element 200 is an eccentric lens, it is possible to freely set the position where a condensed image is formed without depending on the arrangement of the light beam splitting lenses. Has become. Therefore, although the arrangement of the light beam splitting lens 201 in the Y direction (column direction) is zigzag, the corresponding condensed image 20
The arrangement of 3 is linear due to the use of an eccentric lens. As a result, the size (cross-sectional area on the XY plane) of the light beam formed by the collection of the condensed images 203 can be reduced, and the size of the second optical element 300 (described on the XY plane) can be reduced. Cross section), that is, the optical system can be downsized. Further, one polarization separation unit 3 elongated in the Y direction with respect to a series of condensed images (five condensed images surrounded by broken lines in FIG. 2) arranged in the same column direction (Y direction).
Since it is sufficient to make 30 correspond, the configuration of the second optical element 300 can be simplified, and the manufacture becomes easy. The external shape of the light beam splitting lens 201 on the XY plane is set to be similar to the shape of the illumination area 90. In this example, since a horizontally long illumination area is assumed to be long in the X direction on the XY plane, the outer shape of the light beam splitting lens 201 on the XY plane is also horizontally long.

Returning to FIG. 1, the description will be continued. The second optical element 300 includes a condensing lens array 31 as a condensing unit.
0, polarized light separating unit array 3 as polarized light beam separating means
20, a composite substantially composed of a selective retardation plate 380 as a polarization conversion means and a superposition coupling lens 390 as a superposition coupling means, and a condensed image 2 by the first optical element 200
It is arranged in a plane (XY plane in FIG. 1) near the position where 03 is formed and perpendicular to the system optical axis L. The second optical element 300 spatially separates each of the intermediate light beams 202 into a P-polarized light beam and an S-polarized light beam, and then aligns the polarization directions of one polarized light beam and the other polarized light beam, It has a function of guiding each polarized light beam having almost the same polarization direction to one illumination area 90.

As shown in FIG. 4, the condensing lens array 310 includes a plurality of condensing lenses 311, which are eccentric lenses, arranged in a matrix, and a light beam splitting beam constituting the first optical element 200. It is configured using the same number of condenser lenses 311 as the lenses 201. That is, when the first optical element is constituted by a light beam splitting lens composed of M rows × N columns, the condensing lens array similarly has M rows × N
It is composed of a condensing lens composed of rows. The function of the condenser lens array is to convert each intermediate light beam emitted from the first optical element 200 into a polarization separation unit array 320.
Is to efficiently guide the light while condensing it at a specific place.
Therefore, in general, the polarization separation unit array 320
In accordance with the characteristics of the intermediate light beam 202 incident on the polarization separation unit array 320, and further taking into consideration that the inclination of the principal ray is ideally parallel to the system optical axis L. The size and lens characteristics of each condenser lens are optimized. Furthermore, from the viewpoint of miniaturizing the optical system and improving the light use efficiency,
In some cases, the condensing lens array 310 is configured by using a condensing lens whose shape on the XY plane is similar to the light beam splitting lens 201. Therefore, in this example, the same eccentric lens as the light beam splitting lens 201 is used as the condenser lens 311 in consideration of optimization of optical characteristics and cost reduction of the optical system. Unit 3
The incident angle of the intermediate light beam incident on 30 is the most ideal angle (0 degree). The arrangement of the condenser lenses 311 is also set so as to correspond to the arrangement of the condensed images 203 formed by the first optical element 200.
That is, two types of eccentric lenses having different eccentric directions are alternately arranged in the row direction. However, as shown in FIG. 2, since the arrangement of the condensed images in the same column direction (Y direction) is linear, the arrangement of the condenser lenses is also linear in the same column direction. Note that the condenser lens array 310 is not necessarily an essential component, and the characteristics of the intermediate light beam incident on the polarization separation unit array 320, the characteristics and arrangement of the polarization separation unit array, and
It can be omitted depending on the lens characteristics of the superposition coupling lens 390.

Next, the polarization separation unit array 320
As shown in FIG. 5, a plurality of polarization separation units 330 are arranged in the X direction (row direction), and the number of polarization separation units is equal to that of the light beam splitting lens 201 constituting the first optical element 200. It is equal to the number arranged in the X direction.

The appearance of the polarization separation unit 330 is shown in FIG.
As shown in the figure, inside the polarized light beam separating surface 331 and the reflecting surface 33
2 is a rectangular prism-shaped structure elongated in the Y direction, comprising:
It has a function of spatially separating each of the intermediate light beams incident on the polarization separation unit into a P-polarized light beam and an S-polarized light beam. In the case of this example, the size of the polarization splitting unit 330 in the X direction is equal to the size of the light beam splitting lens 201 in the X direction, and the size of the polarization splitting unit 330 in the Y direction is the size of the first optical element 200 in the Y direction. Is set to be equal to the size at. Therefore, one polarization separation unit corresponds to a series (five) of intermediate light beams (condensed images) arranged in the same column direction (Y direction). Needless to say, one polarization splitting unit corresponds to one intermediate light flux, that is, the same number of polarization splitting units as the light splitting lenses 201 constituting the first optical element 200 are provided to the condenser lens array 31.
As in the case of 0, the polarization separation unit array 320 may be configured by arranging in a matrix. However, the size of the polarization separation unit 330 is not necessarily limited to the above set value, and the first optical element 2
It is determined by the overall size of the intermediate light flux (condensed image) formed at 00.

The polarized light beam splitting surface 331 has an inclination of about 45 degrees with respect to the system optical axis L, the reflective surface 332 is parallel to the polarized light beam separating surface 331, and the polarized light beam separating surface 331 is The cross-sectional area projected on the XY plane (equal to the area of a P exit surface 333 described later) and the cross-sectional area projected by the reflecting surface 332 on the XY plane (S exit surface 334 described later)
Are set so that the polarization beam separation surface 331 and the reflection surface 332 are equal. Therefore, in this example, the size Wp in the X direction on the XY plane of the region where the polarized light beam separation surface 331 exists and the size Wm in the X direction on the XY plane of the region where the reflection surface 332 exists.
And each of the polarization separation units 3
30 is equal to half the size W in the X direction on the XY plane. In general, the polarized light beam separating surface can be easily formed by a dielectric multilayer film, and the reflecting surface can be easily formed by a dielectric multilayer film or an aluminum film. By using the dielectric multilayer film, a randomly polarized light beam can be separated into a P-polarized light beam and an S-polarized light beam without light absorption, and a specific polarized light beam can be reflected.

The intermediate light beam 202 incident on the polarization beam splitting unit 330 is reflected on the polarized light beam splitting surface 331 by the P-polarized light beam 335 passing through the polarized light beam separating surface 331 without changing the traveling direction and the polarized light beam separating surface 331. S-polarized light beam 336 that changes its traveling direction in the direction of the adjacent reflecting surface 332
And separated. The P-polarized light beam 335 is directly emitted from the polarization splitting unit via the P-emitting surface 333, and the S-polarized light beam 336 changes its traveling direction again at the reflecting surface 332, and becomes substantially parallel to the P-polarized light beam 335. 334
And is emitted from the polarization separation unit. Therefore, the randomly polarized light beam incident on the polarization separation unit is separated by the polarization separation unit into two types of polarized light beams, P-polarized light beam and S-polarized light beam, whose polarization directions are different from each other. The light is emitted from the emission surface) in substantially the same direction. Since the polarization separation units have the functions described above, each polarization separation unit 330
It is necessary to guide each intermediate light beam 202 to a region where the polarized light beam splitting surface 331 exists. Therefore, each of the polarization beam splitting units is set so that the intermediate light beam enters the center of the polarized light beam splitting surface in the polarized light beam splitting unit. It is necessary to adjust the positional relationship between 330 and each condenser lens 311 and the lens characteristics of each condenser lens 311. In the case of this example, since the centers of the respective condensing lenses (not the optical axes of the lenses) are located at the center of the polarized light beam separating surfaces 331 in the respective polarized light separating units 330, the condensing lenses are arranged. The array 310 has a polarization separation unit X
It is arranged in a state shifted in the X direction with respect to the polarization separation unit array 320 by a distance corresponding to １ ／ of the size in the direction. In addition, from the same viewpoint, the first optical element 200 is separated from the second optical element 3 by a distance corresponding to １ ／ of the size of the light beam splitting lens 201 in the X direction.
1 is displaced in the X direction with respect to 00 (in FIG. 1, only the light beam splitting lens in the third row portion of the first optical element 200 is drawn, The shift amount of the first optical element is the light beam splitting lens 2
01 in the X direction).

A selective retardation plate 380 on which a λ / 2 retardation plate 381 is regularly arranged is provided on the exit surface side of the polarization separation unit array 320. That is, the polarization separation unit 330 constituting the polarization separation unit array 320
The λ / 2 retardation plate 381 is disposed only on the P exit surface 333 of the, and the λ / 2 retardation plate 3 is disposed on the S exit surface 334.
81 is not installed (see FIG. 6). Such λ /
Depending on the arrangement state of the two phase difference plates 381, the P-polarized light beam emitted from the polarization separation unit 330 becomes λ / 2 phase difference plate 3
When passing through 81, it undergoes a rotating action in the direction of polarization and is converted into an S-polarized light beam. On the other hand, since the S-polarized light beam emitted from the S exit surface 334 does not pass through the λ / 2 phase plate 381, the polarization direction does not change and passes through the selected phase plate 380 as the S-polarized light beam. In summary, the polarization separation unit array 320 and the selective retardation plate 380 convert an intermediate light beam having a random polarization direction into one type of polarized light beam (in this case, an S-polarized light beam).

On the side of the exit surface of the selective retardation plate 380, a superposition coupling lens 390 is disposed.
The light beam adjusted to the S-polarized light beam by 80 is guided to the illumination area 90 by the superposition coupling lens 390, and is superposed and coupled on the illumination area. Here, the superposition coupling lens 390 is 1
Need not be two lens bodies, the first optical element 200
As in the above, an aggregate of a plurality of lenses may be used.

The function of the second optical element 300 can be summarized as follows: the intermediate light beam 2 split by the first optical element 200
02 (that is, the image plane cut out by the light beam splitting lens 201) is superimposed and coupled on the illumination area 90 by the second optical element 300. At the same time, the intermediate light beam, which is a random polarized light beam, is spatially separated into two types of polarized light beams having different polarization directions by the polarized light separating unit array 320 on the way, and one type of light beam passes through the selective retardation plate 380. , And almost all light reaches the illumination area 90. Therefore, the illumination area 90 is almost uniformly illuminated with one kind of polarized light beam.

As described above, according to the polarized light illuminating device 1 of the present embodiment, the randomly polarized light beam emitted from the light source unit 10 is transmitted to the first optical element 200 and the second optical element 300.
Has the effect of converting the light into a very large number of light fluxes having almost one kind of polarization direction and uniformly illuminating the illumination area 90 with the light fluxes having the same polarization direction. In particular, in the process of separating the intermediate light beam into two types of polarized light beams, the number of light beams superimposed and coupled on the illumination area is twice as large as the number of intermediate light beams, so that the uniformity of the illumination light in the illumination area is significantly improved. I do. In addition, since almost no light loss occurs in the process of generating the polarized light flux, almost all of the light emitted from the light source unit can be guided to the illumination area 90. It has the characteristic that the efficiency is extremely high.

Further, the light beam splitting lens 201 constituting the first optical element 200 is disposed such that the light beam splitting lens adjacent to the Y direction has a distance corresponding to substantially half the arrangement pitch in the X direction orthogonal to the Y direction. However, since they are arranged so as to be shifted from each other in the X direction, even when the light beam emitted from the light source unit has a very non-uniform intensity distribution, the light beam splitting lens is more than necessary. Without increasing the number of light beams, it is possible to obtain, as illumination light, a high-quality polarized light beam having a very uniform light intensity distribution and its angular distribution on the illumination area 90.

In this embodiment, the condensing lens array 310, the polarization separation unit array 320, the selective phase plate 380, and the superposition coupling lens 39 constituting the second optical element 300 are used.
Numerals 0 are optically integrated, exhibiting the effect of reducing light loss occurring at the interface between them and further increasing light use efficiency.

Further, the illumination area 9 having a horizontally long rectangular shape
0, the light beam splitting lens 201 constituting the first optical element 200 has a horizontally long shape, and at the same time, the two types of polarized light beams emitted from the polarization separation unit array 320 are moved in the horizontal direction (X direction). It is in the form of separation. For this reason, even when illuminating the illumination region 90 having a horizontally long rectangular shape, the illumination efficiency (light use efficiency) can be increased without wasting the light amount.

In general, if a light beam having a random polarization direction is simply separated into a P-polarized light beam and an S-polarized light beam, the width of the entire separated light beam is doubled, and the optical system is correspondingly enlarged. However, in the polarized light illuminating apparatus of the present invention, a plurality of minute condensed images 203 are formed by the first optical element 200, and a space where no light is generated in the process of forming them is effectively used, and the space is polarized. By arranging the reflection surface 332 of the separation unit 330, the spread of the width of the light beam in the horizontal direction caused by separation into two polarized light beams is absorbed, so that the width of the entire light beam does not increase. The feature is that a small optical system can be realized.

(Polarized Lighting Apparatus 2) First Optical Element 200
The size of the condensed image 203 formed by
02 is almost equivalent to the light beam diameter in the state where the light beam diameter is the smallest, and not all the condensed images have the same size and shape. That is, the condensed image formed by the light beam splitting lens located near the light source optical axis R has a large size, and the condensed image formed by the light beam splitting lens located at a peripheral portion distant from the light source optical axis R has a large size. Small dimensions. Therefore, by optimizing the size and shape of each polarization separation unit constituting the polarization separation unit array according to the size and shape of each condensed image formed by the first optical element, the efficiency of the optical system is further improved. As a result, the size of the optical system can be reduced. In this case,
Since the two polarized light beams are separated in the X direction, the efficiency of the optical system can be improved only by optimizing the sizes of the polarized light separating unit in the X direction and the Z direction.

The arrangement of the polarization separation units 330 constituting the polarization separation unit array 320 does not need to be arranged in a parallel positional relationship as in the first embodiment. Therefore, there is a possibility that the efficiency of the optical system can be further improved or the size of the second optical element can be reduced by devising a method of disposing the polarization separation unit.

Further, the size and shape of each condensing lens 311 constituting the condensing lens array 310 on the XY plane are adjusted in accordance with the size of the intermediate light beam incident on each of the corresponding polarization separation units 330. It only has to be set. That is, the dimension of the condenser lens in the X direction is
It is sufficient that at least half or more of the dimension in the X direction of each of the corresponding polarization separation units is arranged.

Therefore, an example of another polarized light illuminating device constructed in consideration of the above points will be described as a polarized light illuminating device 2 with reference to FIG. Note that FIG. 7 is a cross-sectional view in the XZ plane passing through the center of the second optical element 300, similarly to FIG. Further, in the polarized light illuminating device 2 and each of the embodiments described below, since the basic configuration is the same as that of the polarized light illuminating device 1 according to the first embodiment, the portions having the same functions are denoted by the same reference numerals. Therefore, the description is omitted. In the polarized light illuminating device 2 of the present example, the sizes of the respective polarized light separating units and the condenser lens in the X direction are optimized according to the size of the intermediate light beam incident on the polarized light separating unit, and at the same time, the system optical axis L is adjusted. As the symmetry axis, the polarization separation plane is XY
The polarization separation unit is arranged so as to be symmetrical in the plane. Therefore, the basic configuration is almost the same as that of the polarized light illuminating device 1, but the first optical element 200
, The size and shape of each polarization separation unit 330 constituting the polarization separation unit array 320, the arrangement thereof, and the dimension of the λ / 2 phase difference plate 381 constituting the selected phase difference plate 380. The shape and its arrangement state, the configuration of the superposition coupling lens 390,
The positional relationship between the light source unit 10 and the first optical element 200 with respect to the polarization separation unit array 320 is slightly different from that of the polarized light illumination device 1.

The polarization separation unit array 320 of the present example
It is configured by using two types of polarization separation units L340 and S341 having different dimensions in the X direction and the Z direction (the dimensions in the Y direction are the same). That is, the polarization separation unit L340 located near the system optical axis L has large dimensions in the X direction and the Z direction so as to be able to cope with a large condensed image, while being located at a peripheral portion away from the system optical axis L. Since the polarization separation unit S341 only needs to be able to cope with a condensed image having a small size, the dimensions in the X and Z directions are small. When the size of the polarization separation unit is changed according to the location, the polarization separation is performed such that the polarization beam separation surface 331 is symmetrical in the XY plane with the system optical axis L as the axis of symmetry. By arranging the units, it is generally easy to configure the optical system.

Further, the selective retardation plate 380 disposed on the side of the exit surface of the polarization separation unit array 320 is also arranged on the XY plane of the λ / 2 retardation plate so as to correspond to the size of the polarization separation unit 330. The size has been optimized.
That is, a selected phase difference plate in which a large λ / 2 phase difference plate L382 is arranged near the system optical axis L, and a small size small λ / 2 phase difference plate S383 is arranged around the system optical axis L. 380 is used. Further, the superposition coupling lens 39 arranged on the side of the exit surface of the selective retardation plate 380
Reference numeral 0 is a complex lens composed of a plurality of lenses having different sizes and lens characteristics so as to correspond to the size of the polarization separation unit 330.

Of course, as in the case of the polarized light illumination device 1 of the first embodiment, both the light beam splitting lens 201 and the condenser lens 311 are decentered lenses, and the intermediate light beam 202 formed by the first optical element 200 is Each of the lenses is optimized so that it can be efficiently incident on each polarization separation unit 330.

By adopting the above configuration,
Since each intermediate light beam 202 (condensed image 203) formed by the first optical element 200 can be almost completely taken into the second optical element 300, almost no light loss occurs in the process of generating the polarized light beam. Therefore, the utilization efficiency of the light source light can be further improved. In addition, since the dimensions of the polarization separation unit 330 and the condenser lens 311 in the XY plane are optimized to the minimum necessary size, the second optical element 300 can be reduced in size and the cost can be reduced. is there.

(Display Device Using Polarization Lighting Apparatus 1) An example of a direct-view type display apparatus incorporating the polarization lighting apparatus 1 will be described. In this example, a transmissive liquid crystal panel is used as a modulating means for modulating a light beam emitted from the polarized light illuminating device based on display information.

FIG. 8 is a schematic configuration diagram showing a main part of an optical system of the display device 3 of the present example, and shows a cross-sectional structure in the YZ plane. The display device 3 of the present example includes the polarization illuminating device 1, the reflection mirror 510, and the liquid crystal panel 520 illustrated in FIG.
Approximately.

The polarized light illuminating device 1 includes a light source unit 10 for emitting a randomly polarized light beam in one direction.
Is converted into almost one kind of polarized light beam. The polarized light beam emitted from the polarized light illumination device 1 is reflected by a reflection mirror 510.
The direction of light can be bent about 90 degrees by the
20 is illuminated with approximately one type of polarized light beam. Polarizing plates 521 are arranged before and after the liquid crystal panel. Note that a light guide (for example, an optical fiber) may be used instead of the reflection mirror, and a light diffusion plate is arranged in front of the liquid crystal panel 520 (on the reflection mirror 510 side) for the purpose of improving the viewing angle. Is also good.

In the display device 3 configured as described above, a liquid crystal panel that modulates one kind of polarized light beam is used. Therefore, when a randomly polarized light beam is guided to a liquid crystal panel using a conventional lighting device, about half of the random polarized light beam is absorbed by the polarizing plate 521 and converted into heat, and the light utilization efficiency is increased. There was a problem that was bad. However, in the display device 3 of the present example, such a problem is greatly improved.

That is, in the display device 3 of the present embodiment, in the polarized light illuminating device 1, only one polarized light beam (for example, P-polarized light beam) is given a rotating action of the polarization plane by the λ / 2 retardation plate, and the other is. (For example, S-polarized light beam) and the polarization direction are aligned. Therefore, almost one kind of polarized light beam having a uniform polarization direction is guided to the liquid crystal panel 520.
Light absorption by the polarizing plate 521 is extremely small, and therefore, the efficiency of use of light from the light source is improved, and a bright display state can be obtained.

Further, in the polarized light illuminating device 1 constituting the display device 3 of the present embodiment, the light beam splitting lens 201 forming the first optical element 200 is replaced with the light beam splitting lens adjacent to the Y direction in the direction orthogonal to the Y direction. Are arranged so as to be shifted from each other in the X direction by a distance corresponding to substantially half the arrangement pitch in the X direction, and the illumination is performed in the process of separating the intermediate light beam into two types of polarized light beams. When the number of light beams superimposed and coupled on the liquid crystal panel 520, which is a region, is 2
Since the light intensity distribution and the angular distribution are extremely uniform on the liquid crystal panel, it is possible to obtain high-quality illumination light, and therefore, a bright high-quality display state with less brightness unevenness and color unevenness can be obtained. Obtainable.

Although the polarization illuminating device 1 of the first embodiment is used in the display device 3 of the present embodiment, it goes without saying that the polarization illuminating device 2 of the second embodiment can be used instead.

(First Example of Projection Display Device Using Polarization Lighting Device 1) A first example of a projection display device incorporating the polarization lighting device 1 shown in Embodiment 1 will be described.
In this example, a transmissive liquid crystal panel is used as a modulating means for modulating a light beam emitted from the polarized light illuminating device based on display information.

FIG. 9 is a schematic configuration diagram showing a main part of an optical system of the projection display device 4 of the present example, and shows a configuration in the XZ plane. The projection display device 4 of the present embodiment is similar to the projection display device of the first embodiment
, A polarized light illuminating device, color light separating means for separating a white light beam into three color lights, three transmissive liquid crystal panels for modulating each color light based on display information and forming a display image,
A color light combining means for combining three color lights to form a color image and a projection optical system for projecting and displaying the color image.

The polarized light illuminating device 1 of this embodiment includes a light source unit 10 for emitting a randomly polarized light beam in one direction. Is converted into a polarized light beam.

The light beam emitted from the polarized light illuminating device 1 first transmits red light and reflects blue light and green light in a blue light green light reflecting dichroic mirror 801 as color light separating means. The red light is reflected by the reflection mirror 802 and reaches the liquid crystal panel 803 for red light. On the other hand, of the blue light and the green light, the green light is reflected by the green light reflecting dichroic mirror 804, which is also a color light separating means, and reaches the green light liquid crystal panel 805.

Here, since blue light has the longest optical path length of each color light, the blue
6, a light guiding means 850 composed of a relay lens system including a relay lens 808 and an emission lens 810 is provided. That is, after transmitting the blue light through the green light reflecting dichroic mirror 804, the blue light is first guided to the relay lens 808 via the incident lens 806 and the reflecting mirror 807,
After being focused on this relay lens, it is guided to the emission lens 810 by the reflection mirror 809, and then reaches the blue light liquid crystal panel 811. Here, the three liquid crystal panels 803, 805, and 811 modulate the respective color lights and include image information corresponding to the respective color lights, and then input the modulated color lights to the cross dichroic prism 813 which is a color light synthesis unit. I do. In the cross dichroic prism 813, a dielectric multilayer film for reflecting red light and a dielectric multilayer film for reflecting blue light are formed in a cross shape, and the modulated light beams are combined to form a color image. The color image formed here is enlarged and projected on a screen 815 by a projection lens 814 as a projection optical system to form a projection image.

In the projection display device 4 configured as described above, a liquid crystal panel that modulates one kind of polarized light beam is used. Therefore, when a randomly polarized light beam is guided to a liquid crystal panel using a conventional lighting device, about half of the randomly polarized light beam is absorbed by a polarizing plate (not shown) and turned into heat. In addition, there is a problem that the light use efficiency is low and a large and noisy cooling device for suppressing heat generation of the polarizing plate is required. However, in the projection display device 4 of the present embodiment, such a problem is greatly improved.

That is, in the projection display device 4 of the present embodiment, in the polarized light illuminating device 1, only one polarized light beam (for example, a P-polarized light beam) is rotated by a λ / 2 retardation plate to rotate the polarization plane. The polarization direction of the other polarized light beam (for example, S-polarized light beam) is aligned. Therefore, almost one kind of polarized luminous flux having a uniform polarization direction is supplied to three liquid crystal panels 803,
Since the light is guided to 805 and 811, the light absorption by the polarizing plate is very small, so that the light use efficiency is improved and a bright projected image can be obtained. In addition, since the amount of light absorbed by the polarizing plate is reduced, temperature rise in the polarizing plate is suppressed,
Therefore, the cooling device can be reduced in size and noise can be reduced, and a high-performance projection display device can be realized.

Further, in the projection display device 4 of this embodiment, the cross dichroic prism 813 is used as the color light combining means. The cross dichroic prism 813 is composed of a red light reflecting dielectric multilayer film and a blue light reflecting dielectric film. Since it is a composite composed of four right-angle prisms formed with a body multilayer film, large light scattering locally occurs at the boundary surface where the right-angle prisms are joined in a cross shape. Therefore,
When a projection type display device is configured using this cross dichroic prism, the central part of the projected image becomes vertically dark due to local light scattering generated at the central part of the cross dichroic prism, which is very obstructive. There was a problem of becoming. In order to solve this problem, it is necessary to increase the homogeneity of the light passing through the cross dichroic prism (to make the light intensity distribution and its angular distribution uniform), that is, it is necessary to improve the light illuminating the liquid crystal panel. Is nothing less than improving the homogeneity of On the other hand, in the projection display device 4 of the present embodiment, such a problem is greatly improved.

That is, in the polarized light illuminating device 1 constituting the projection type display device 4 of this embodiment, the light beam splitting lens 201 forming the first optical element 200 is replaced by the light beam splitting lens adjacent in the Y direction. And distributing the intermediate light beam into two types of polarized light beams while displacing each other in the X direction by a distance corresponding to substantially half the array pitch in the X direction orthogonal to the X direction. Since the number of luminous fluxes superimposed and coupled on each of the liquid crystal panels 803, 805, and 811 as illumination regions is doubled, the light intensity distribution and its angular distribution on each of the liquid crystal panels 803, 805, and 811 are extremely low. Uniform high-quality illumination light can be obtained. In order to form a projection image using the illumination light having high homogeneity of the light, the cross dichroic prism 8 is used.
13, the effect of local light scattering can be avoided, and a high-quality image can be displayed on the screen 815 without the central part of the projected image becoming dark in the vertical direction.

Further, in the polarized light illuminating device 1, the two kinds of polarized light beams are spatially separated in the horizontal direction (X direction) in the second optical element 300. Therefore, it is convenient to illuminate a horizontally long rectangular liquid crystal panel without wasting light.

As described in connection with the first embodiment, in the polarized light illuminating apparatus 1 of the present embodiment, the polarization separation unit array 320 is included although the polarization conversion optical element is incorporated.
The spread of the width of the light beam that emits light is suppressed. This means that when illuminating the liquid crystal panel, almost no light enters the liquid crystal panel with a large angle. Therefore, a bright projected image can be realized without using a large-diameter and expensive projection lens having a small F-number, and as a result, a small-sized projection display device can be realized.

In this embodiment, since the cross dichroic prism 813 is used as the color light combining means,
The size of the device can be reduced. In addition, a liquid crystal panel 802,
Since the length of the optical path between 805 and 811 and the projection lens system is short, a bright projection image can be realized even if an inexpensive projection lens having a relatively small aperture is used. Each color light is 3
Although only one of the optical paths has a different optical path length, in this example, for the blue light having the longest optical path length, the incident lens 8 is used.
Since there is provided the light guiding means 850 composed of a relay lens system composed of the optical lens 06, a relay lens 808, and an emission lens 810, color unevenness does not occur.

The projection type display device can be constituted by a mirror optical system using two dichroic mirrors as color light combining means. Of course, even in that case, the polarized light illuminating device of this example can be incorporated, and a bright high-quality projected image with excellent light use efficiency can be formed as in the case of this example.

Finally, the polarization illuminating device 1 of the first embodiment is used in the projection type display device 4 of the present embodiment, but it goes without saying that the polarization illuminating device 2 of the second embodiment can be used instead.

(Second Example of Projection Display Using Polarization Lighting Apparatus 1) A second example of a projection display incorporating the polarization lighting apparatus 1 will be described. In this example, a reflection type liquid crystal panel is used as a modulating means for modulating a light beam emitted from the polarized light illuminating device based on display information.

FIG. 10 is a schematic structural view of a main part of the optical system of the projection display device 5 of this embodiment, as viewed in plan. The projection display device 5 of the present example includes the polarization illuminating device 1, the polarization beam splitter 860, the cross dichroic prism 813 that also serves as a color light separating unit and a color light combining unit, and three reflective liquid crystals serving as modulation units. It is roughly composed of a panel and a projection lens 814 as a projection optical system.

The polarized light illuminating device 1 of this embodiment includes a light source unit 10 for emitting a randomly polarized light beam in one direction, and a random polarized light beam emitted from the light source unit 10 is almost one type by a polarization generator 20. (In this example, an S-polarized light beam).

The light beam emitted from the polarized light illuminating device 1 enters the polarizing beam splitter 860, is reflected by the polarization separating surface 861, is changed in traveling direction by approximately 90 degrees, and is incident on the adjacent cross dichroic prism 813. Here, most of the light beam emitted from the polarized light illumination device 1 is an S-polarized light beam, but a slightly polarized light beam (P-polarized light beam in this example) having a different polarization direction from the S-polarized light beam is mixed. The polarized light beams having different polarization directions (P-polarized light beams) pass through the polarization splitting surface 861 as they are and are emitted from the polarization beam splitter 860 (the P-polarized light beams are different from the illumination light for illuminating the liquid crystal panel). No).

The S-polarized light beam incident on the cross dichroic prism 813 is separated by the cross dichroic prism into three light beams of red light, green light, and blue light according to the wavelength, and the corresponding reflective liquid crystal panels for red light. 871, a reflective liquid crystal panel 872 for green light, and a reflective liquid crystal panel 873 for blue light, and illuminates the respective liquid crystal panels. That is, the cross dichroic prism 8
Reference numeral 13 functions as a color light separating unit for illuminating light for illuminating the liquid crystal panel.

Here, the liquid crystal panel 87 used in this example is
Since each of the liquid crystal panels 1, 872, and 873 is a reflection type, each liquid crystal panel modulates each color light to include display information from the outside corresponding to each color light, and at the same time, a light flux emitted from each liquid crystal panel. Are changed, and the traveling direction of the light beam is substantially reversed. Therefore, the reflected light from each liquid crystal panel is emitted in a partially P-polarized state according to the display information. The modulated light flux (mainly a P-polarized light flux) emitted from each liquid crystal panel is again applied to the cross dichroic prism 8.
13, are combined into one optical image, and are again incident on the adjacent polarizing beam splitter 860. That is, the cross dichroic prism 813 functions as a color light combining unit for the modulated light flux emitted from the liquid crystal panel.

Among the light beams incident on the polarization beam splitter 860, the light beam modulated by the liquid crystal panels 871, 872, and 873 is a P-polarized light beam, and therefore passes through the polarization splitting surface 861 of the polarization beam splitter 860 without change.
A projection image is formed on a screen 815 via a projection lens 814.

In the projection display device 5 configured as described above, as in the case of the projection display device 4 described above, a liquid crystal panel of a type that modulates one kind of polarized light beam is used. In the case of using a conventional illumination device using polarized light as illumination light, as described in the fourth embodiment, there is a problem in that light utilization efficiency is low and it is difficult to obtain a bright projected image. However, in the projection display device 5 of the present example, such a problem is greatly improved.

That is, in the projection display device 5 of this example, by using the polarized light illuminating device 1 of the present invention instead of the conventional illuminating device, it is possible to efficiently generate almost one kind of polarized luminous flux having a uniform polarization direction. Yes, therefore, the polarizing beam splitter 860
, Almost all of the light flux is guided to three reflective liquid crystal panels 871, 872, 873 as illumination light flux. Therefore, light use efficiency is improved,
It is possible to obtain a projected image which is bright and free from brightness unevenness and color unevenness.

In the projection display device 5 of this embodiment, the cross dichroic prism is used as the color light separating means and the color light synthesizing means. However, as described in the fourth embodiment, the structure of the cross dichroic prism is limited. The degradation of the quality of the projected image due to local light scattering caused by the problem described above is greatly improved by increasing the homogeneity of the light illuminating the liquid crystal panel.

That is, in the polarized light illuminating device 1 constituting the projection display device 5 of this embodiment, the first optical element 200
Are separated from each other in the X direction by a distance corresponding to almost half the arrangement pitch in the X direction orthogonal to the Y direction in the light beam splitting lenses adjacent to each other in the Y direction. And the number of light beams superimposed and coupled on each liquid crystal panel, which is an illumination area, in the process of separating the intermediate light beam into two types of polarized light beams is doubled. As described above, it is possible to obtain high-quality illumination light having a very uniform light intensity distribution and its angular distribution. Since the projection image is formed by using the illumination light having high homogeneity of the light, the influence of local light scattering in the cross dichroic prism 813 can be avoided, and the central portion of the projection image is not darkened in the vertical direction. A high-quality image can be projected on the screen 815.

As described above, in the polarized light illuminating apparatus 1 of the present embodiment, the spread of the light beam emitted from the polarized light separating unit array 320 is suppressed, despite incorporating the polarization conversion optical element. . This means that when illuminating the liquid crystal panel, almost no light enters the liquid crystal panel with a large angle. Therefore, a bright projected image can be realized without using a large-diameter and expensive projection lens having a small F-number, and as a result, a small-sized projection display device can be realized.

In this example, a cross dichroic prism is used as the color light separating means and the color light synthesizing means. However, a projection type display apparatus can be constructed by using two dichroic mirrors instead. Of course, in this case as well, the polarized light illuminating device of the present embodiment can be incorporated, and a bright and high-quality projected image excellent in light use efficiency can be formed as in the case of the present embodiment.

[0115]

As described above, the optical element of the present invention can generate a specific polarized light beam with extremely high efficiency, and can generate a polarized light beam having uniform brightness and no color unevenness. It is possible to get.

In the polarized light generator of the present invention, the light intensity distribution and its angular distribution in the illumination area are more uniform than those of the incident light beam from the incident light beam, which is a random polarized light beam, and the polarization directions are almost uniform. The outgoing light beam can be generated with very high efficiency.

Further, the display device and the projection type display device of the present invention can obtain a very uniform image over the display surface and the entire projection surface.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an optical system of a polarized light illuminating device 1 which is an example of a polarized light illuminating device using the polarized light generating device of the present invention.

FIG. 2 is a perspective view of a first optical element of the polarized light illumination device 1.

FIG. 3 is a diagram showing a position of a lens optical axis of each light beam splitting lens constituting a first optical element of the polarized light illumination device 1.

FIG. 4 is a perspective view of a condenser lens array of the polarized light illumination device 1.

FIG. 5 is a perspective view of a polarized light separation unit array of the polarized light illumination device 1.

FIG. 6 is a diagram for explaining a function of a polarization separation unit of the polarized light illumination device 1.

FIG. 7 is a schematic configuration diagram showing an optical system of a polarized light illuminating device 2 which is a second example of the polarized light illuminating device using the polarized light generating device of the present invention.

FIG. 8 is a schematic configuration diagram of an optical system showing an example of a display device in which the polarized light illumination device 1 is incorporated.

FIG. 9 is a schematic configuration diagram of an optical system showing an example of a projection display device in which the polarized light illumination device 1 is incorporated.

FIG. 10 is a schematic configuration diagram of an optical system showing a second example of a projection display device in which the polarized light illumination device 1 is incorporated.

FIG. 11 is a schematic configuration diagram of a polarization optical system disclosed in Japanese Patent Application Laid-Open No. 7-294906.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 2 Polarization illumination device 3 Display device 4, 5 Projection display device 10 Light source part 20 Polarization generator 90 Illumination area 101 Light source lamp 102 Parabolic reflector 200 First optical element 201 Beam splitting lens 202 Intermediate beam 203 Condensing Image 204 Lens optical axis 205 Lens center 300 Second optical element 310 Condensing lens array 311 Condensing lens 320 Polarization separation unit array 330 Polarization separation unit 331 Polarized light beam separation surface 332 Reflection surface 333 P emission surface 334 S emission surface 335 P Polarized light beam 336 S-polarized light beam 340 Polarization separation unit L 341 Polarization separation unit S 380 Selective phase difference plate 381 λ / 2 phase difference plate 382 λ / 2 phase difference plate L 383 λ / 2 phase difference plate S 390 Superposition coupling lens 510, 802, 807, 809 Reflecting mirror 520, 9 0 Liquid crystal panel 521 Polarizing plate 801 Blue light green light reflecting dichroic mirror 803 Red light liquid crystal panel 804 Green light reflecting dichroic mirror 805 Green light liquid crystal panel 806 Incident lens 808 Relay lens 810 Outgoing lens 811 Blue light liquid crystal panel 813 Cross dichroic prism 814 Projection Lens 815 Screen 850 Light guide means 860 Polarization beam splitter 861 Polarization separation surface 871 Reflection type liquid crystal panel for red light 872 Reflection type liquid crystal panel for green light 873 Reflection type liquid crystal panel for blue light 910 Lens plate 920 Polarization beam splitter 930 Reflection prism 940 λ / 2 phase difference plate

Claims (18)

[Claims] 1. A first optical element for condensing an incident light beam and converting it into a plurality of intermediate light beams spatially separated from each other, and a second optical element disposed near a position where the intermediate light beam converges. Wherein the first optical element comprises a plurality of light beam splitting lenses arranged in a matrix, each of the plurality of light beam splitting lenses is an eccentric lens, and a light beam splitting lens adjacent in the column direction. Are arranged so as to be shifted from each other in the row direction, and the second optical element spatially separates each of the intermediate light beams into an S-polarized light beam and a P-polarized light beam and emits them. The P-polarized light beam emitted from the polarized light beam separating means,
A polarization conversion unit that converts one of the S-polarized light beams into the other polarization direction, and the other polarized light beam, and the one polarized light beam whose polarization direction is converted by the polarization conversion unit. And a superimposing and coupling means for superimposing and coupling the light into an outgoing light beam. 2. The polarized light beam separating means according to claim 1, wherein the polarized light beam separating means includes a reflecting surface and a polarized light beam separating surface, and the reflecting surface and the polarized light beam separating surface are arranged in parallel with each other. Polarization generator. 3. The polarization generator according to claim 1, wherein the outer shape of the light beam splitting lens is rectangular. 4. The optical system according to claim 1, wherein the second optical element further includes a light condensing means for condensing the plurality of intermediate light beams, and the light condensing means is a matrix. A polarization generator comprising a plurality of condenser lenses arranged in a shape. 5. The polarization generator according to claim 4, wherein each of the plurality of condenser lenses is an eccentric lens. 6. A light source unit, a first optical element that collects a light beam from the light source unit and converts the light beam into a plurality of intermediate light beams spatially separated from each other, and near a position where the intermediate light beam converges. A display device comprising: a second optical element arranged; and a modulation unit that modulates a light beam emitted from the second optical element, wherein the first optical element includes a plurality of first optical elements arranged in a matrix. Wherein each of the plurality of light beam splitting lenses is an eccentric lens, and the light beam splitting lenses adjacent in the column direction are arranged in a state shifted from each other in the row direction, and the second optical element A polarized light beam separating unit that spatially separates each of the intermediate light beams into an S-polarized light beam and a P-polarized light beam and emits the light; the P-polarized light beam emitted from the polarized light beam separating device;
A polarization conversion unit that converts one of the S-polarized light beams into the other polarization direction, and the other polarized light beam, and the one polarized light beam whose polarization direction is converted by the polarization conversion unit. And superimposing and coupling means for superimposing and coupling the light into an output light beam. 7. The polarized light beam separating means according to claim 6, wherein the polarized light beam separating means includes a reflecting surface and a polarized light beam separating surface, and the reflecting surface and the polarized light beam separating surface are arranged in parallel with each other. Display device. 8. A light source unit, a first optical element that collects light beams from the light source unit and converts them into a plurality of intermediate light beams spatially separated from each other, and near a position where the intermediate light beams converge. A projection display apparatus comprising: a second optical element disposed; a modulating unit that modulates a light beam emitted from the second optical element; and a projection optical unit that projects a light beam modulated by the modulating unit. The first optical element includes a plurality of light beam splitting lenses arranged in a matrix. Each of the plurality of light beam splitting lenses is an eccentric lens, and a light beam splitting lens adjacent in the column direction. The second optical element is arranged so as to be shifted from each other in the row direction, and the second optical element spatially separates each of the intermediate light beams into an S-polarized light beam and a P-polarized light beam, and emits the polarized light beam; Polarized light beam The P-polarized light beam emitted from the release means,
A polarization conversion unit that converts one of the S-polarized light beams into the other polarization direction, and the other polarized light beam, and the one polarized light beam whose polarization direction is converted by the polarization conversion unit. And superimposing and coupling means for superimposing and coupling the light into an output light beam. 9. The polarization beam splitting means according to claim 8, wherein the polarized light beam separating means includes a reflecting surface and a polarized light beam separating surface, and the reflecting surface and the polarized light beam separating surface are arranged in parallel with each other. Polarization generator. 10. The optical device according to claim 8, wherein the second optical element further includes a light condensing means for condensing the plurality of intermediate light beams, and the light condensing means is arranged in a matrix. A projection display device comprising: a plurality of condensing lenses. 11. The projection display according to claim 10, wherein each of the plurality of condenser lenses is an eccentric lens. 12. The light source unit according to claim 8, wherein, of the plurality of polarized light beam separating units, the size of the polarized light beam separating unit located near the optical axis of the light source unit is smaller than that of the light source unit. A projection type display device, wherein the size of the polarized light beam separating means located in a peripheral portion distant from the optical axis is larger. 13. A light source unit, a first optical element that collects light beams from the light source unit and converts them into a plurality of intermediate light beams spatially separated from each other, and near a position where the intermediate light beams converge. A second optical element disposed; a color light separating unit configured to separate a light beam emitted from the second optical element into two or more color lights; and a plurality of color light beams provided from the color light separating unit. Projection-type display device, comprising: two or more of the above-mentioned modulating units; a color-light synthesizing unit that synthesizes the color lights modulated by the respective modulating units; Wherein the first optical element includes a plurality of light beam splitting lenses arranged in a matrix, and each of the plurality of light beam splitting lenses is an eccentric lens, and is adjacent in the column direction. The light beam splitting lenses are arranged so as to be shifted from each other in the row direction, and the second optical element spatially separates each of the intermediate light beams into an S-polarized light beam and a P-polarized light beam and emits them. Means, the P-polarized light beam emitted from the polarized light beam separating means,
A polarization conversion unit that converts one polarization direction of the polarized light beam into the other polarization direction, and the other polarized light beam and the one polarized light beam whose polarization direction is converted by the polarization conversion unit are superimposed. And a superimposing coupling means for coupling the light into an emitted light beam. 14. The polarization beam splitting means according to claim 13, wherein the polarized light beam separating means includes a reflecting surface and a polarized light beam separating surface, and the reflecting surface and the polarized light beam separating surface are arranged in parallel with each other. Polarization generator. 15. The device according to claim 13, wherein the second optical element further includes a light condensing means for condensing the plurality of intermediate light beams, and the light condensing means is arranged in a matrix. A projection display device comprising: a plurality of condensing lenses. 16. The projection display according to claim 15, wherein each of the plurality of condenser lenses is an eccentric lens. 17. The light source unit according to claim 13, wherein, among the plurality of polarized light beam separating units, the size of the polarized light beam separating unit located near the optical axis of the light source unit is smaller than that of the light source unit. A projection type display device, wherein the size of the polarized light beam separating means located in a peripheral portion distant from the optical axis is larger. 18. The projection type display device according to claim 13, wherein said color light combining means comprises a cross dichroic prism in which dichroic films are arranged in a cross shape.