JPH11142792A - Polarizing device and projection type display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To illuminate a light valve with high luminance and to provide a projection image with high luminance by arranging a glass rod in the middle part of a prism array composed of only a polarizing beam splitter and the glass rod. SOLUTION: An almost parallel light beam from a light source part 1 is made incident on a lens plate 2 arranging lenses 2a in a plane, divided into light beams determined by an aperture formed by the lenses 2a and passed through the lenses 3a of a lens plate 3 set on the focal positions of the respective lenses 2a. In a prism array 4 arranged closely to the exit plane of the lens plate 3, a polarizing beam splitters(PBS) 6 are arranged on both sides of a glass rod 5 arranged in the boudary part of the lens 3a on the optical axis 0 and a glass rod 7 is arranged on both sides of the PBS 6. A half wavelength plate 50 is stuck to the exit planes of the glass rod 5 and PBS 6 and the mixed light of randomly polarizing light transmitted through the glass rod 5 and S polarizing light through PBS 6 and the half wavelength plate 50 are transmitted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polarizing device used for a polarized light illuminating device of a liquid crystal light valve used in a projection type display device, and a light valve illuminated by the polarized light illuminating device using the polarized light device. The present invention relates to a projection display device that projects emitted modulated light as an image on a screen.

[0002]

2. Description of the Related Art Hitherto, as a method for uniformly illuminating a rectangular illumination area such as a liquid crystal light valve, an illumination apparatus using a so-called fly-eye integrator using two lens plates has been known.

In order to further improve the illumination efficiency of this illumination device, a polarizing beam splitter array and a half-wave plate are arranged at predetermined positions on a second exit surface of the two lens plates. There has been proposed a polarization illuminating device aiming at utilization efficiency of light from a light source and a projection type display device using the illuminating device (JP-A-8-30473).
No. 9).

FIG. 6 shows FIG. 8 in the above publication which is used as a description of a polarizing device and a projection type display device described as a modification of the fifth embodiment of the above publication.

[0005] The conventional example shown in FIG.
0 and a parabolic reflector 10 which is a concave mirror such as a parabolic mirror
1 form a light source unit 102, and a substantially parallel light beam emitted from the light source unit 102 enters a first lens plate 104 on which a plurality of lenses 103 are arranged in a plane. Then, the light emitted from the first lens plate 104 is
The light enters the plurality of lenses 106 of the lens plate 105. In this case, since each lens 106 of the second lens plate 105 is formed corresponding to the shape of each lens 103 of the first lens plate 104 and is arranged at the focal position of these lenses 103, Light from each lens 103 of the first lens plate 104 is focused on the lens 106 of the second lens plate 105.

A plurality of polarizing beam splitters (hereinafter referred to as “PBS”) are provided on the exit surface side of the second lens plate 105.
That. ) 107 is disposed, and a polarizing beam splitter array (hereinafter, referred to as a “PBS array”) 108 is disposed.
On the emission surface of the PBS array 108, a half-wave plate 109 is arranged every other PBS 107. Further, a condenser lens 110 is arranged on the exit surface side of the half-wave plate 109.

According to the drawing, the substantially parallel light beam incident on the lens 103 of the first lens plate 104 is condensed on the substantially central portion of the lens 106 of the second lens plate 105 as described above, and exits the lens 106. , P constituting the PBS array 108
The P-polarized light that enters the BS 107, passes through the polarization separation unit 107a disposed obliquely of the PBS 107, and exits as it is, is reflected by the polarization separation unit 107a of the PBS 107, and enters the adjacent PBS 107.
It is polarized and separated into polarized light. The S-polarized light that has entered the adjacent PBS 107 is polarized by the polarization separation unit 1 of the PBS 107.
07a, and is emitted in the same direction as the optical axis incident on the lens 106.

A half-wave plate 109 is disposed on the exit surface of the PBS 107 and the P-polarized light exit surface. P-polarized light incident on the half-wave plate 109 is converted into S-polarized light. As a result, all the incident light source light is emitted as S-polarized light.

The S-polarized light enters the light valve 111 via the condenser lens 110, so that the light valve 111 is efficiently illuminated.

In such a case, by disposing the PBS array 108, the half-wave plate 109, and the like,
Certainly, the first lens plate 104 and the second lens plate 105
Compared to a lighting device that uses only S-polarized light, it is possible to achieve much higher brightness in terms of polarized light illumination to the light valve 111.

In other words, in the method using the first lens plate 104 and the second lens plate 105 and not using the PBS array 108 or the like, since the randomly polarized light is illuminated on the light valve 111, Is used as incident light because it is linearly polarized light in one direction.

[0012]

However, the demand for higher brightness of a projected image of a recent projection type display device has not been stopped, and further higher brightness has been demanded.

[0013] In this respect, the polarized light illuminating device in the conventional method is not always satisfactory as described later, and the present inventors have studied this polarized light illuminating device as a comprehensive polarizing device including a light source section. It has been found that the function inherent in the polarizing device is not sufficiently exhibited.

SUMMARY OF THE INVENTION It is an object of the present invention to sufficiently exhibit the inherent functions of the conventional method and to achieve even higher brightness polarized illumination.

[0015]

In view of such a problem, the invention described in claim 1 is a light source unit and a lens plate in which a plurality of lenses are arranged in a plane, and the light source unit emits light from the light source unit. A first lens plate that divides the light of the light source into a light flux determined by an aperture formed by the plurality of lenses, and another lens plate that has a plurality of lenses in a planar manner,
A second lens plate in which the plurality of lenses of the lens plate respectively form bright spots on the plurality of lenses of the other lens plate, and light emitted from individual bright spots of the plurality of lenses of the second lens plate. An incident prism array, wherein the prism array includes a polarization beam splitter having substantially a polarization splitting portion and a prism array substantially including only a glass rod, and the polarization beam splitter forming the prism array. One of the P-polarized light or the S-polarized light that is disposed on the emission surface and is polarized and separated by the polarization beam splitter that configures the prism array and that is emitted from the bright spot incident on the prism array and exits the prism array. 1 / for converting polarized light into the other polarized light
A polarizing device including a two-wave plate, wherein the substantial glass rod is disposed in the center of the prism array.

According to a second aspect of the present invention, there is provided a polarizing device including a light source unit, and P-polarized light or S-polarized light emitted from the polarizing device.
A color separation optical system that separates polarized light into R light, G light, and B light; a light valve that is arranged for each color light that emits each color light by the color separation optical system by modulating each color light with a signal of each color light; An analysis optical system that detects modulated light from the light emitted from the light valve of each color light, a synthesis optical system that performs color synthesis of each color analysis light by the analysis optical system, and projects the synthesized light by the synthesis optical system. And a projection optical system, wherein the polarizing device is a lens plate in which a light source unit and a plurality of lenses are arranged in a plane, and the light source unit emits light emitted from the light source unit to the plurality of lenses. A first lens plate for splitting into a light beam determined by the aperture defined by the above, and another lens plate having a plurality of lenses in a plane, wherein each of the plurality of lenses of the first lens plate is the other lens plate Bright spots on multiple lenses A second lens plate, and a prism array to which light emitted from individual bright points of a plurality of lenses of the second lens plate is incident, wherein the prism array substantially has a polarization splitting unit. A prism array comprising a polarization beam splitter and substantially only a glass rod; and a prism arranged on the exit surface of the polarization beam splitter that constitutes the prism array, the prism outputting light emitted from the bright spot incident on the prism array. A polarizing device comprising: a half-wave plate for converting one of P-polarized light or S-polarized light that has been polarized and separated by the polarizing beam splitter constituting the array and emitted from the prism array to the other polarized light. The projection display device is a polarizing device in which the substantial glass rod is disposed at the center of the prism array. And wherein the door.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [Analysis of Conventional Method for Achieving the Present Invention] FIG. 7 shows a reflection type light valve 112 and a polarizing beam splitter 113 of a polarization illuminating device according to a conventional method.
FIG. 1 is an explanatory diagram of a configuration of a projection type display device equipped with.

According to the description of FIG. 1, light source light incident on the optical axes of the first and second lens plates 104 and 105 is condensed on the lens 106 of the second lens plate 105 and is focused on the center of the lens 106. It is described that small bright spots are formed.

However, the present inventors have stated that the center of the first lens plate 104 and the second lens plate 105 in the above-mentioned conventional polarizing device is as described in the conventional example (forming a small bright spot). Instead, the two lenses 10 sandwiching the optical axis at the substantially central portion of the second lens plate 105, which is a sectional configuration diagram
With regard to No. 6, it was found by an experiment that the size of the bright spot substantially covers the entire opening formed by the two lenses 106.

This is because the light source lamp 100 of the light source unit 102
Is not a point light source as described in the description of the conventional example above, but has a finite size in fact. In practice, the second lens is formed by the lens 103 of the first lens plate 104 in FIG. A bright spot having a large area is formed substantially at the center of the plate 105 centered on the optical axis.

That is, the light flux does not enter the lens 103 disposed substantially at the center of the first lens plate 104 around the optical axis, but enters the lens 103 with a predetermined inclination. This is the cause, and as a result, the light beam incident on the lens 103 enters the corresponding lens 106 of the second lens plate 105 as a luminescent point of the entire aperture formed by the lens 106.

Further, the light beam emitted from the large area luminescent spot formed on the entire lens 106 around the optical axis of the second lens plate 105 occupies most of the light beam emitted from the entire second lens plate 105.

That is, as shown in FIG. 6, a light beam emitted from a luminescent spot formed substantially at the center of the lens 106 near the center of the second lens plate 105 is as described in the conventional example. And the adjacent PBS array 108
S-polarized light that is incident on the PBS 107 and transmitted through the polarization separation unit 107a, and is polarized by the half-wave plate 109 disposed on the exit surface.
The PBS 107 is reflected, enters the adjacent PBS 107, and the same S-polarized light is emitted by the polarization splitting unit 107a of the PBS 107.

On the other hand, since there is a large bright spot around the optical axis of the second lens plate 105 as described above, the second lens plate 105 also has a bright spot near the optical axis and at the boundary of the lens 106 as shown in FIG. Light incident from one lens plate 104 is present and forms a bright spot. The luminous flux emitted from these bright spots is a problem.

That is, as shown in FIG. 7, the light emitted from the bright spot enters the proximity PBS 107 and is
Although the light passes through the polarization splitting unit 107a of the BS 107,
Since the wavelength plate 109 is not disposed, the P-polarized light is emitted as it is, while the S-polarized light reflected by the polarization splitting unit 107a is incident on the adjacent PBS 107 and is polarized.
Is reflected and converted by the half-wave plate 109 disposed on the exit surface to emit P-polarized light. This P-polarized light passes through the polarization beam splitter 113 and cannot contribute to the illumination of the reflective light valve 112. Further, even if the light valve 112 is a transmissive light valve 114 as described in the projection display device of the above-mentioned conventional publication, the light valve 112 is absorbed by the S-polarized light transmitting polarizing plate disposed on the incident side of the light valve 114. Thus, the illumination light of the light valve 114, that is, the projection light is not effectively used, and the high brightness of the projection image is not sufficiently satisfied.

Based on such an analysis, an embodiment of the invention for solving the above-mentioned problem will be described below.

[First Embodiment of the Invention] FIGS.
FIG. 1 is a diagram illustrating a polarization device according to a first embodiment of the present invention and a projection display device employing the same.

According to FIG. 1, a light source unit 1 comprises a lamp 1a and a concave mirror 1b comprising a parabolic mirror, and a substantially parallel light beam emitted from the light source unit 1 is supplied to an infrared absorption filter (not shown). Further, the light is incident on the first lens plate 2 on which the lens 2a is arranged in a plane via the ultraviolet absorption filter, and is divided into light beams determined by the openings formed by the individual lenses 2a of the first lens plate 2. You.
Then, the light beam is incident on the second lens plate 3.

The second lens plate 3 has a plurality of lenses 3a.
Are arranged in a plane, these lenses 3a are arranged corresponding to the individual lenses 2a of the first lens plate 2, and are set at the focal positions of the respective lenses 2a.

Each of the lenses 2a and 3a is formed of 4 × 5 pixels, and the first lens plate 2 and the second lens
A so-called fly-eye integrator is constituted by the lens plate 3.

The light from the light source passing through the lens 2a of the first lens plate 2 is transmitted to the corresponding second lens plate 3 as described above.
Through the lens 3a, and is incident on the prism array 4 arranged close to or adhered to the exit surface of the second lens plate 3.

As shown in FIG. 4 and the like, the prism array 4 includes a first glass rod 5 disposed on the optical axis O (the center in the width direction) at the boundary of the lens 3a along the vertical direction. And two PBSs 6 arranged on both sides of the glass rod 5 and second glass rods 7 arranged on both sides of the PBS 6.

A half-wave plate 50 is attached to the first glass rod 5 and the exit surface of each PBS 6 on both sides thereof.

Therefore, the randomly polarized light transmitted through the first glass rod 5 and the PBS 6 and the half-wave plate 50
And the mixed light with the S-polarized light is emitted.

This mixed light is incident on the cross dichroic mirror 11 via the condenser lens 8. The cross dichroic mirror 11 is arranged such that the B light reflecting dichroic mirror 10 and the G and R light reflecting dichroic mirrors 9 are orthogonal to each other and are incident at an angle of 45 degrees with respect to the incident optical axis. The cross dichroic mirror 11 performs color separation into R light and G and R mixed light, which are parallel to each other and have opposite optical axes.

The color-separated B light is transmitted to the bending mirror 1
The light then travels with the optical axis changed to a right angle by 2, and is incident on the B light polarization beam splitter 13B provided with a polarization separation unit so that S polarized light of the B light is reflected and P polarized light is transmitted.

On the other hand, the R and G mixed light travels while changing the optical axis to a right angle by the bending mirror 14, and the G light is arranged on the optical axis at an incident angle of 45 degrees with respect to the incident optical axis. The G light that is incident on the light reflecting dichroic mirror 15 and is reflected and travels while changing the optical axis to a right angle, and the R light that travels as it is
Color separated into light and light.

That is, the dichroic mirrors 9 and 10
And a dichroic mirror 15 to constitute a “color separation optical system” that separates the light into R, G, and B light.

The color-separated G light and R light are polarized light splitters 13G for G light in which a polarization separation section is disposed so that S-polarized light is reflected and P-polarized light is transmitted.
In addition, the light enters the polarization beam splitter 13R for R light.

The polarization beam splitters 13B, 1 for each color light
3G, 13R, and enters the polarization beam splitter 13
A light valve 16B for B light, a light valve 16G for G light, and a light valve 16R for R light are arranged near the S-polarized light exit surface of each color that reflects and emits B, 13G, and 13R, respectively.

The light valves 16R, 16G, and 16B used in this embodiment are reflection valves of the electric writing type, and only the portions where the incident polarized light (S-polarized light) of a predetermined pixel portion is selected by each color signal. As the modulated light (P-polarized light), the non-selected portion has a function of reflecting and emitting the same S-polarized light as the incident light.

Each color light valve 16R, 16G, 1
6B are again incident on the polarization beam splitters 13B, 13G, and 13R for each color light, and only the modulated light is transmitted by the polarization splitters of the polarization beam splitters 13B, 13G, and 13R to perform analysis and emission. The unmodulated light is reflected and discarded. The polarization beam splitters 13B, 13G, and 13R constitute an "analysis optical system" that detects modulated light from light emitted from the light valves 16R, 16G, and 16B for each color light. Then, the respective color analysis lights are incident on the cross dichroic prisms 18 constituting the “combining optical system” from different incident surfaces, respectively, and perform color combining.

This cross dichroic prism 18
Has a B light reflecting dichroic film 18B and R
A prism in which the light reflecting dichroic films 18R are arranged so as to be orthogonal to each other. The R light and the B light, which are the analysis light, incident on the prism 18, are reflected by the dichroic film 18R and the dichroic film 18B and The optical axis is changed to a right angle, the light beams travel in the same direction, and emerge from the prism 18.

On the other hand, the analysis light of the G light passes through the two dichroic films 18B and 18R as it is, and proceeds as described above.
By traveling and exiting in the same optical axis direction as B light,
The color synthesis of the R, G, B light is achieved.

The combined light is incident on a projection lens 19 constituting a “projection optical system” and projected on a screen (not shown) as a full-color image.

The above is the configuration of the projection type display device according to the present invention.

Here, the polarizing device according to the present invention will be described in more detail with reference to FIGS.

FIG. 4 shows the second embodiment of the polarizing device according to the present invention.
Lens plate 3, prism array 4, and half-wave plate 7
Is a perspective view as viewed from the exit surface side of the member.

The lens 3a of the second lens plate 3 has a 4 × 5 array as described above, and a columnar body having a square cross section is provided on the exit surface side of the lens plate 3 in the vertical direction. First along
A glass rod 5, a PBS 6 having the same shape as the first glass rod 5, and a prism array 4 having a second glass rod 7 which is a columnar body having a rectangular cross section and extends along the vertical direction are arranged. In this prism array 4, the side surfaces of the adjacent first glass rod 5, PBS 6 and second glass rod 7 are adhered to each other, and from one side, one second glass rod 7, two PBS 6, and one first glass rod 5. Glass rod 5, 2 PBS
6, one second glass rod 7 is arranged in this order.
Further, two PBSs 6 arranged on both sides of the optical axis O are provided.
Is such that the direction of arrangement of the polarization splitting section 6a is 4 degrees with respect to the incident light so that the S-polarized light reflected by the polarization splitting section 6a in the incident light is reflected outward with respect to the optical axis O.
They are arranged with an inclination of 5 °.

The width of the first glass rod 5 or PBS 6 is half the width of the lens 3a of the lens plate 3, and the position of the first glass rod 5 is the optical axis O.
Above, the PBS 6 is disposed corresponding to the boundary position of the lens 3a of the second lens plate 3, and the PBSs 6 adjacent to both sides of the first glass rod 5 are disposed so as to coincide with the central portion of the lens 3a. I have. Further, the PBSs 6 adjacent on both sides of the PBS 6 are arranged corresponding to the boundary positions of the lenses 3a. Further, the second glass rod 7 has P
It is formed 1.5 times wider than BS6.

The first glass rod 5 at the center of the exit surface of the prism array 4 and the exit surface of one PBS 6 disposed on both sides of the first glass rod 5, as shown by hatching in FIG.
The half-wave plate 50 is adhered and arranged.

Further, the polarizing device and the projection type display device of the present invention will be described with reference to FIGS.

FIG. 2 and FIG. 3 are front sectional views of a projection type display device using the polarization device, and show the polarization type device and the condenser lens 8 of the projection type display device at the position of the optical axis O.
The polarization beam splitter 13 and the light valve 16 are illustrated, and further, a ray diagram is illustrated.

As a projection type display device, R light, G light and B light should be described as shown in FIG. 1, but the light valves 16B, 16G and 16 are used for each color light.
Since the optical path lengths to R are all the same, the description of the color separation optical system is omitted, and as described above, each light valve 16
B, 16G, and 16R are illustrated as light valves 16, and the polarization beam splitters 13B, 13G, and 13R for each color light are illustrated as the polarization beam splitter 13.

According to this figure, the substantially parallel light source light emitted from the light source unit 1a is transmitted to the first lens plate 2 as described above.
And the lens 2a (consisting of 4 × 5) that constitutes the lens plate 2
Are divided into a plurality of light fluxes by the opening formed by the aperture, and each of the split light fluxes is incident on the lens 3a constituting the second lens plate 3 corresponding to the lens 2a, as described above. With respect to approximately four lenses 3a around the optical axis O of the second lens plate 3, unlike the outer peripheral portion due to the influence of the lamp 1a and the like, a bright point only at the central portion of the lens 3a does not occur. Have a spread, and the amount of light of these bright spots has almost all of the light incident on the second lens plate 3.

The second lens plate 3 adjacent to the optical axis O in FIG.
For the lens 3a, a bright spot having a high luminance is generated on the entire surface. Of the bright spots, light emitted from the bright spot substantially at the center of the lens 3a enters the PBS 6 and is polarized and separated. 1 / which is transmitted through the portion 6a and disposed on the PBS6 emission surface.
The light is converted into S-polarized light by the two-wavelength plate 50 and emitted.

On the other hand, the S-polarized light reflected by the polarization splitting portion 6a of the PBS 6 is incident on the adjacent PBS 6, and is reflected by the polarization splitting portion 6a of the PBS 6, but the emission surface has a half-wave plate. Since 50 is not arranged, the light is emitted as S-polarized light as it is.

The S-polarized light enters the polarization beam splitter 13 via the condenser lens 8, and is reflected and emitted because the polarization splitting portion of the polarization beam splitter 13 is configured to reflect the S-polarized light. Then, the light enters the reflection type light valve 16 disposed near the exit surface of the polarization beam splitter 13 to illuminate the light valve 16.

On the other hand, as shown in FIG. 3, the light emitted from the luminescent spot on the optical axis O portion (substantially at the center) of the luminescent spot around the optical axis O of the second lens plate 3 is arranged closely. The light is incident on the first glass rod 5 disposed at the center of the prism array 4. The glass rod 5 is a rod having a square cross section, and the emitted light incident on the rod is emitted as it is and passes through the half-wave plate 50, but the polarization state changes due to the randomly polarized light. The P-polarized light component is transmitted through the condenser lens 8 and is emitted through the condenser lens 8, and is transmitted through the polarization splitter 13, and is discarded. The S-polarized light reflected by the polarization splitter is reflected. The light is emitted to illuminate the light valve 16.

In view of this, the half-wave plate 50 is not necessarily required on the exit surface of the first glass rod 5, but the half-wave plate 50 is disposed except for the relevant portion. In the first embodiment, one half-wavelength plate 5
0 is attached to the front surface.

Further, in FIG. 2, the lens 3a adjacent to the optical axis O and the outermost lens 3a
Of the light incident on the boundary portion of the condenser lens 8
Is incident on the polarization beam splitter 13 via
It cannot contribute to the illumination of the light valve 16 because of the P-polarized light.

However, there are almost no bright spots on the lens 3a in this portion, and as described above, the bright spot portion formed at the position of the lens 3a adjacent to the optical axis O has an absolute light quantity. In many cases, the illumination light of the light pulp 16 does not decrease. On the other hand, the fact that half of the light emitted from the bright spot near the optical axis O according to the present invention can be used as the illumination light for the light valve 16 is higher than that the high-intensity illumination of the light valve 16 can be achieved. A great effect that a projection image of luminance can be projected can be obtained.

[Second Embodiment of the Invention] FIG. 5 is a structural explanatory view of a projection type display apparatus according to a second embodiment of the present invention.

The prism array 4 differs from the polarizing device according to the first embodiment shown in FIGS. 1 to 4 in that the first glass rod 5 having a square cross section in the first embodiment.
And the PBS 6 or the rectangular second glass rod 7 is adhered in a plane, but in the second embodiment, the prism array 24 having the irregular shape is used to substantially perform the previous operation. The same function as in the first embodiment can be exhibited. The same components as those in the first embodiment are illustrated using the same reference numerals.

This prism array 24 has five prisms 25, 26, 27, 28, 29, and a polarization separation film 30 between these prisms 25, 26, 27, 28, 29.
Is provided.

More specifically, the prisms 25 and 29 arranged on both sides of the prism array 24 are the same as the second glass rod 7 of the first embodiment and the triangular prism on one side obtained by separating the PBS 6 from the polarization splitting section 6a. Have a trapezoidal shape with a substantially matched cross section.

The prisms 26 and 28 adjacent to the inside of the prisms 25 and 29 are connected to the prisms 25 and 2 respectively.
It has the same thickness as 9 and has a parallelogram cross section,
It has substantially the same shape as the combined shape of the two triangular prisms bonded to each other of the two PBSs 6 joined together in the first embodiment.

Further, the central prism 27 arranged on the optical axis O has a trapezoidal cross section, and the first glass rod 5 of the first embodiment and the P glass adhered to both side surfaces thereof.
The shape is substantially the same as the shape obtained by combining the triangular prisms on one side of BS6.

Then, these five prisms 25, 2
The prism array 24 according to the second embodiment is formed by forming a polarization separation film 30 on one of the inclined surfaces 6, 27, 28, and 29 and then bonding it with an adhesive to form a plane.

On the entire exit surface of the prism 27, 1 /
The arrangement of the two-wavelength plate 50 is the same as in the first embodiment.

By using the prism array 24 of the present invention, it is possible to achieve the same effect as in the first embodiment, achieve illumination of the high-brightness light valve 16, and provide a projection display device capable of projecting a high-brightness projection image. The effect that it can be provided can be similarly exhibited.

In the second embodiment, an irregularly shaped prism array 24 is used, and the portion of the central prism 27 corresponding to the first glass rod 5 of the first embodiment is substantially the same as that described in the claims. Glass rod ".
Further, a part (triangular part) on both sides of the prism 27, a part (triangular part) inside the prisms 26 and 28, the prisms 25 and 29, and the polarization separation unit 30 are the first embodiment.
, And corresponds to a “polarization beam splitter having substantially a polarization separation section” described in the claims.

In the projection type display device using the polarization device according to the first and second embodiments, the illumination light to the light valve 16 is S-polarized light reflected by the polarization splitting portion of the polarization beam splitter 13 as incident illumination. However, the light valve 16 may be illuminated with the P-polarized light transmitted through the polarization splitting unit. In that case, it is necessary to configure the polarizing device so that the polarized light to be emitted is mostly P-polarized light. To this end, the position where the half-wave plate 50 is disposed is set to 1 in each of the above embodiments. This can be achieved by not arranging the half-wave plate 50 at the place where the half-wave plate 50 is arranged, but arranging the half-wave plate 50 at the place where the half-wave plate 50 is not arranged.

Further, in each of the first and second embodiments, the lens 3a of the second lens plate 3 constituting the polarizer is formed 4 × 5 horizontally, and 2 × 2 regions near the optical axis O are formed. This is an embodiment in a case where a high-luminance area is generated over the entire area. This high-luminance area does not depend on the size, arrangement, and the like of the lenses 2a, 3a of the first lens plate 2 and the second lens plate 3, and for example, further includes the first lens plate 2 and the second lens plate 2.
When the number of lenses 2a, 3a of the lens plate 3 is increased, the number of lenses 3a included in the high-luminance area further increases, and the prism array 4
Is increased, but the region of the high luminance portion does not substantially change substantially in the second lens plate 3. Therefore, the prism arrays 4, 24
Of the first glass rods 5 and the prisms 25 and 2
Needless to say, the size and the like of 9 also change accordingly.

Further, a case has been described in which the polarizing devices according to the first and second embodiments of the present invention are employed in the projection type display device shown in FIG. 1. However, the projection type display device using the polarizing device of the present invention is described above. It goes without saying that the present invention is not limited to the projection type display device having the configuration described above.

Further, the "color separation optical system" is also configured so as to become B light and R light which are reflected by the cross dichroic mirror and color-separated to the opposite side, and G light which passes through the cross dichroic mirror. Alternatively, a “color separation optical system” having another configuration may be used. Moreover, the light valve 16 to be used does not need to be limited to the reflection type, and a transmission type light valve may be used.

[0077]

As described above, according to the invention described in each of the claims, the substantially central portion of the second lens plate is located closer to the peripheral portion than the central portion of the lens constituting the lens plate. In view of the fact that the light amount distribution is higher, a substantial glass rod is arranged at the center of the prism array, so that in the conventional method, light emitted from a portion corresponding to the portion cannot illuminate the light valve. On the other hand, light emitted from the portion can be used as illumination light for the light valve. As a result, it is possible to achieve high-luminance illumination of the light valve, and to obtain a great effect that a high-luminance projected image can be obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating a polarizing device and a projection display device according to a first embodiment of the present invention.

FIG. 2 is a ray diagram illustrating illumination of a light valve using the polarizing device according to the first embodiment.

FIG. 3 is another ray diagram to a light valve using the polarizing device according to the first embodiment.

FIG. 4 is a view showing 1/1 used in the polarizing device according to the first embodiment.
FIG. 4 is a perspective view of a bism array including a two-wavelength plate and a second lens plate.

FIG. 5 is an explanatory view of illumination of a light valve using a prism array in which a half-wave plate used in a polarizing device according to a second embodiment of the present invention is arranged.

FIG. 6 is an illumination light diagram for a conventional polarizing device and a light valve.

FIG. 7 is a ray diagram for explaining a problem of a conventional polarizing device.

[Explanation of symbols]

 Reference Signs List 1 light source unit 2 first lens plate 2a lens forming first lens plate 3 second lens plate 3a lens forming second lens plate 4,24 prism array 5 first glass rod 6 PBS 6a forming prism array Polarization Separation unit 7 Second glass rod 8 Condenser lens 9,10,11,15 Dichroic mirror (color separation optical system) 12,14 Bending mirror 13,13R, 13G, 13B Polarization beam splitter (analysis optical system) 16,16R , 16G, 16B Light valve 18 Cross dichroic prism (synthetic optical system) 19 Projection lens (projection optical system) 25,26,27,28,29 Prism 30 Polarization separation unit 50 1/2 wavelength plate

Claims (2)

[Claims] 1. A lens plate in which a light source unit and a plurality of lenses are arranged in a plane, and wherein a light source emitted from the light source unit is divided into light beams determined by openings formed by the plurality of lenses. One lens plate and another lens plate having a plurality of lenses in a plane,
A plurality of lenses of the first lens plate each forming a luminescent spot on a plurality of lenses of the other lens plate; and a plurality of lenses emitted from the respective luminescent spots of the plurality of lenses of the second lens plate. A prism array to which the incident light is incident, the prism array being substantially composed of a polarizing beam splitter having a polarization splitting section and a glass rod substantially only, and the prism array constituting the prism array Of the P-polarized light or S-polarized light that is disposed on the polarization beam splitter emission surface and is polarized and separated by the polarization beam splitter constituting the prism array, the light emitted from the bright spot incident on the prism array is emitted from the prism array. And a half-wave plate for converting one polarized light into the other polarized light. The central portion, polarization apparatus characterized by said substantially glass rod is arranged. 2. A polarizing device including a light source unit, and P-polarized light or S-polarized light emitted from the polarizing device is converted into R light, G light,
A color separation optical system that separates the light into B light, a light valve that is arranged for each color light that modulates and emits each color light by the signal of the color light by the color separation optical system, and a light valve for each color light. An analyzing optical system for analyzing modulated light from the emitted light, a combining optical system for combining colors of each color analyzing light by the analyzing optical system, and a projection optical system for projecting combined light by the combining optical system. In the projection type display device, the polarizing device is a lens plate in which a light source unit and a plurality of lenses are arranged in a plane, and the light source light emitted from the light source unit is determined by an aperture formed by the plurality of lenses. A first lens plate for splitting the light beam to be split, and another lens plate having a plurality of lenses in a plane,
A plurality of lenses of the first lens plate each forming a luminescent spot on a plurality of lenses of the other lens plate; and a plurality of lenses emitted from the respective luminescent spots of the plurality of lenses of the second lens plate. A prism array to which the incident light is incident, the prism array being substantially composed of a polarizing beam splitter having a polarization splitting section and a glass rod substantially only, and the prism array constituting the prism array Of the P-polarized light or S-polarized light that is disposed on the polarization beam splitter emission surface and is polarized and separated by the polarization beam splitter constituting the prism array, the light emitted from the bright spot incident on the prism array is emitted from the prism array. And a half-wave plate for converting one polarized light into the other polarized light. The central portion, a projection display device, characterized in that said substantially glass rod was placed polarizer.