JP2004286937A - Display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To attain highly precise display picture by preventing blur between adjacent pixels on an irradiated object. <P>SOLUTION: In a display device 1 which makes image light, coming from irradiating light from a light source 2 and spatial light and modulated with a reflection type spatial light modulator 6, be subjected to a shift of its optical path and be displayed on the irradiated object 9, a polarization dependent lens array 5, having polarization dependency of the irradiating light and the image light different from each other, is disposed between a polarization separating element 4, polarization separating the irradiating light and the image light, and the reflection type spatial light modulator 6. By setting the lens power of the polarization dependent lens array 5 intensifying the image light than for the irradiating light, the highly precise display picture is attained by preventing the blur between the adjacent pixels on the irradiated object 9. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a display device.
[0002]
[Prior art]
There is a display device in which irradiation light from a light source is spatially modulated by a spatial light modulator in accordance with image data to be displayed, and the spatially modulated light is enlarged and displayed on a screen or the like.
[0003]
In such a display device, a display frame is composed of a plurality of sub-frames, and the spatial light modulator switches and displays an image for each sub-frame, and performs spatial light modulation corresponding to the image switching for each sub-frame. There is an image display device that deflects image light that has been spatially modulated by a display device so that the image of each subframe is shifted on a screen and displayed.
[0004]
In addition, there is a display device in which the image is shifted on the screen by changing the polarization direction of the image light in a plurality of directions while a single display frame is displayed by the spatial light modulator.
[0005]
The spatial light modulator used in such a display device is of a transmission type that performs spatial light modulation when transmitting irradiation light from a light source, and performs spatial light modulation when reflecting irradiation light from a light source. There is a reflection type.
[0006]
[Problems to be solved by the invention]
By the way, in a display device using a reflection type spatial light modulator (reflection type spatial light modulator), an incident light incident on the reflection type spatial light modulator and an image spatially modulated by the reflection type spatial light modulator are used. The optical path with light partially overlaps.
[0007]
In the above-described conventional technology, when a transmission-type spatial light modulator is used, high definition of an image can be achieved. However, when a reflection-type spatial light modulator is used, sufficient high definition can be achieved. It is difficult to plan.
[0008]
SUMMARY OF THE INVENTION It is an object of the present invention to suppress blurring between adjacent pixels in an image displayed by a display device using a reflective spatial light modulator, and to improve the definition of a displayed image.
[0009]
[Means for Solving the Problems]
The display device according to the first aspect of the present invention includes a light source that emits irradiation light, a reflective spatial light modulator that reflects image light obtained by spatially modulating the irradiation light emitted by the light source using a plurality of pixels, Display control means for switching and displaying an image in units of sub-frames obtained by dividing a display frame into a plurality of frames for the reflective spatial light modulator, and irradiating light emitted from the light source and spatially reflecting the reflected spatial light modulator. A polarization separating element for polarizing and separating the light modulated image light, an optical path shifting means for shifting the image light separated by the polarization separating element in response to switching of display by the display control means, and an image after the optical path shift A magnifying optical system for magnifying and projecting light onto an irradiation target, and a light-emitting element, which is provided between the reflective spatial light modulator and the polarization splitting element, has different polarization dependencies on the irradiation light and the image light. Yes A polarization-dependent element that comprises a.
[0010]
Therefore, by using the reflection type spatial light modulator, even when the light paths of the irradiation light and the image light partially overlap, each light path can be individually handled according to the polarization state. Accordingly, it is possible to suppress bleeding between adjacent pixels in an image displayed by the display device using the reflective spatial light modulator, and to increase the definition of the display image.
[0011]
According to a second aspect of the present invention, in the display device according to the first aspect, the polarization-dependent member is associated with each pixel of the reflective spatial light modulator, and the image light is more than the lens power for the irradiation light. The lens has a lens power set to be larger than that of the lens.
[0012]
Therefore, it is possible to make the optical path of the irradiation light different from that of the image light even though the reflective spatial light modulator is used.
[0013]
According to a third aspect of the present invention, in the display device of the second aspect, the polarization dependent member is formed of an optically transparent uniaxial anisotropic material.
[0014]
Therefore, it is possible to easily produce a polarization-dependent member having the effect of the second aspect.
[0015]
According to a fourth aspect of the present invention, in the display device according to the third aspect, the polarization-dependent member is configured such that lenses corresponding to respective pixels of the reflective spatial light modulator are arranged in an array, and the reflective spatial light is It has a lens array substrate placed in contact with the modulator.
[0016]
Therefore, the image light spatially modulated by the reflection type spatial light modulator is surely made incident on the polarization dependent member, and the image light spatially modulated by each pixel is prevented from being incident on the lens adjacent to the corresponding lens. Therefore, the light use efficiency can be improved and the display image can be made higher definition. In addition, by arranging the polarization dependent member and the reflective spatial light modulator in contact, the size of the device can be reduced.
[0017]
According to a fifth aspect of the present invention, in the display device according to the second aspect, the polarization dependent member includes a lens array substrate on which lenses corresponding to each pixel of the reflective spatial light modulator are arranged in an array. It is composed of an optically transparent flat plate facing the lens array substrate and a uniaxial anisotropic material filled between the lens array substrate and the flat plate.
[0018]
Therefore, a polarization-dependent lens array exhibiting the effect of the invention described in claim 2 can be easily manufactured.
[0019]
The invention according to claim 6 is the display device according to claim 5, wherein the uniaxial anisotropic material has an ordinary light refractive index or an extraordinary light refractive index equal to the refractive index of the lens array substrate.
[0020]
Therefore, it is possible to eliminate the lens power for the irradiation light and to exert the lens power only for the image light, and it is possible to further enhance the definition of the displayed image.
[0021]
According to a seventh aspect of the present invention, in the display device according to the second aspect, the polarization dependent member includes a pair of lens array substrates in which lenses corresponding to respective pixels of the reflective spatial light modulator are arranged in an array. And a uniaxial anisotropic material filled between the lens array substrates.
[0022]
Therefore, it is possible to improve the productivity of the polarization dependent lens array having the function of the invention described in claim 2.
[0023]
The invention according to claim 8 is the display device according to claim 7, wherein the uniaxial anisotropic material has an ordinary light refractive index or an extraordinary light refractive index equal to the refractive index of at least one of the lens array substrates.
[0024]
Therefore, it is possible to eliminate the lens power for the irradiation light and to exert the lens power only for the image light, and it is possible to further enhance the definition of the displayed image.
[0025]
According to a ninth aspect of the present invention, in the display device according to any one of the fourth to seventh aspects, the uniaxial anisotropic material is a liquid crystal filled between a pair of optically transparent substrates. .
[0026]
Therefore, the liquid crystal can be filled between the substrates sandwiching the liquid crystal without a gap, so that the polarization-dependent lens array does not increase in size, and as compared with the case where a uniaxial anisotropic material in a crystalline state is used. The work of processing the uniaxial anisotropic material itself into a lens array structure can be eliminated.
[0027]
According to a tenth aspect of the present invention, in the display device according to the ninth aspect, an electrode provided on each of the substrates included in the polarization dependent member, a voltage application unit configured to apply a voltage to the electrode, and Voltage adjusting means for adjusting a voltage value applied by the applying means.
[0028]
By the way, since the orientation distribution of the irradiation light emitted from the light source varies, and the dispersion occurs when assembling the display device, the projection performance of the irradiation light, the light use efficiency, and the like may vary.
[0029]
Therefore, the lens power of the polarization-dependent lens array can be adjusted by adjusting the voltage applied to the electrodes, so that variations in the projection performance of irradiation light, light use efficiency, and the like can be suppressed.
[0030]
According to an eleventh aspect of the present invention, in the display device according to the ninth or tenth aspect, the reflective spatial light modulator performs spatial light modulation by changing the orientation of a liquid crystal filled between a pair of optically transparent substrates. The substrate in the polarization dependent member also serves as the substrate for supporting the liquid crystal in the reflective spatial light modulator.
[0031]
Therefore, the image light spatially modulated by the reflection type spatial light modulator can be surely made incident on the polarization dependent lens array, and the incidence on the adjacent lens can be suppressed. Can achieve higher definition. Further, the size of the device can be reduced by using the substrate supporting the liquid crystal in the reflective spatial light modulator for the polarization dependent lens array.
[0032]
According to a twelfth aspect of the present invention, in the display device according to the ninth or tenth aspect, the substrate in the polarization dependent member has a convex or concave lens shape, and a refractive index of the lens array substrate is an extraordinary light of a uniaxial anisotropic material. It is set equal to the refractive index or the ordinary light refractive index.
[0033]
Therefore, it is possible to realize a polarization-dependent lens array that exerts a convex lens power on image light.
[0034]
According to a thirteenth aspect of the present invention, in the display device according to the ninth or tenth aspect, a polarization direction of light incident on the polarization dependent member from the polarization separation element is parallel or perpendicular to an optical axis of the uniaxial anisotropic material. The refractive index of the substrate is set to be equal to the extraordinary or ordinary light refractive index of the uniaxial anisotropic material.
[0035]
Therefore, it is possible to realize a polarization-dependent lens array that exerts a convex lens power on image light.
[0036]
BEST MODE FOR CARRYING OUT THE INVENTION
A first embodiment of the present invention will be described with reference to FIGS. This embodiment shows an example of application to a display device that displays a projection image on a screen or the like.
[0037]
First, the optical system configuration of the entire display device of the present embodiment will be described. FIG. 1 is a schematic diagram showing an optical system configuration of the entire display device of the present embodiment. As shown in FIG. 1, the display device 1 includes a light source unit 2, an irradiation optical system 3, a polarization separation element 4, a polarization dependent lens array 5, a reflective spatial light modulator 6, a pixel shift element 7, and a projection unit 8. Have. The irradiation optical system 3, the polarization separation element 4, the polarization dependent lens array 5, the reflection type spatial light modulator 6, the pixel shift element 7, and the projection unit 8 are arranged on an optical path 10 for guiding the light emitted from the light source unit 2 to a screen 9. It is provided in.
[0038]
The light source unit 2 includes a light source 11 that emits light, and a parabolic mirror 12 that irradiates light emitted from the light source 11 in one direction. The description of the light source unit 2 is omitted because it is a known technique.
[0039]
The irradiation optical system 3 includes fly-eye lens arrays 13 and 14 and a condenser lens 15. The irradiation optical system 3 equalizes the light emitted from the light source unit 2 by the fly-eye lens arrays 13 and 14 and condenses the light by the condenser lens 15.
[0040]
The polarization separation element 4 transmits light polarized in a certain direction and reflects light polarized in a direction orthogonal to the polarization direction. In the present embodiment, a polarization beam splitter is used as the polarization splitting element 4. Hereinafter, the polarization beam splitter will be described with reference numeral 4. The polarizing beam splitter 4 of the present embodiment transmits light polarized in the vertical direction on the paper of FIG. 1 and reflects light polarized on the front and back of the paper of FIG. This makes it possible to separate the irradiation light emitted from the light source unit 2 toward the reflective spatial light modulator 6 and the image light spatially modulated by the reflective spatial light modulator 6.
[0041]
The reflective spatial light modulator 6 has a plurality of pixels arranged in an array, and selectively turns on / off each pixel to spatially modulate irradiation light to generate image light. . The reflection type spatial light modulator 6 gives the image light a phase difference of λ / 2 with respect to the irradiation light, and rotates the polarization direction by 90 °.
[0042]
In the present embodiment, a reflective liquid crystal panel is used as the reflective spatial light modulator 6. Although not shown or described in detail because it is a known technique, the reflection type spatial light modulator includes a liquid crystal cell including a pair of substrates and a liquid crystal sandwiched between the substrates. . The substrate is provided with a plurality of transistors and electrodes for driving liquid crystal (both not shown). A driver is connected to these liquid crystal driving transistors and electrodes. The driver is driven and controlled by a display control circuit (not shown) to control spatial light modulation by the reflective spatial light modulator 6. Here, a function as a display control unit is realized.
[0043]
The pixel shift element 7 shifts the image light reflected by the polarization beam splitter 4 in accordance with the sub-frame. Here, an optical path shifting means is realized. Note that the pixel shift element 7 that shifts and emits the incident light is a known technique, and a description thereof will be omitted.
[0044]
The projection unit 8 enlarges and displays the image light transmitted through the pixel shifting element 7 toward a screen. Here, a magnifying optical system is realized by the projection unit 8. For example, a magnifying lens can be used as the projection unit 8.
[0045]
Next, the polarization dependent lens array 5 will be described. In the present embodiment, a polarization dependent member is realized by the polarization dependent lens array 5. The polarization-dependent lens array 5 is provided between the reflective spatial light modulator 6 and the polarization beam splitter 4, and is configured by arranging a plurality of polarization-dependent lenses in an array. Each lens in the polarization dependent lens array 5 is arranged corresponding to each pixel in the reflective spatial light modulator 6. The polarization dependent lens array 5 has different polarization dependences on the irradiation light irradiated from the polarization beam splitter 4 side and the image light spatially modulated by the reflection type spatial light modulator 6. I have.
[0046]
In the polarization-dependent lens array 5 of the present embodiment, the lens power for the image light is set to be larger than the lens power for the irradiation light by making the radius of curvature for the irradiation light different from that for the image light. I have.
[0047]
Although not particularly shown, the display device 1 of the present embodiment includes a control system that drives and controls each unit included in the display device 1. The above-described reflective spatial light modulator 6, the pixel shift element 7, and the like include the control system. Drive control is performed based on a computer program stored in a computer provided in the control system.
[0048]
In such a configuration, the irradiation light emitted from the light source unit 2 is homogenized and condensed by the irradiation optical system 3 and is incident on the polarization beam splitter 4. The polarizing beam splitter 4 transmits light polarized in the vertical direction on the paper and irradiates the light to the reflective spatial light modulator 6.
[0049]
The reflective spatial light modulator 6 is driven and controlled by the control unit, and spatially modulates the incident irradiation light on a display frame basis. By this spatial light modulation, image light polarized in the front and back directions of the paper is generated. The reflective spatial light modulator 6 generates a phase difference of λ / 2 in image light reflected by being spatially modulated with respect to the incident irradiation light, and rotates the polarization direction by 90 °.
[0050]
The pixel shift element 7 is driven and controlled by the control unit, and shifts image light spatially modulated by the reflective spatial light modulator 6. At this time, the pixel shift element 7 shifts the image light so that the image light projected on the screen is shifted by an arbitrary distance in the pixel arrangement direction. In the present embodiment, while the spatial light modulation of a single display frame is performed by the reflective spatial light modulator 6, the irradiation positions of the image light projected on the screen 9 are radiated to four places that do not overlap each other. Thus, the image light is shifted.
[0051]
The projection lens 8 enlarges the image light deflected by the pixel shift element 7 and projects the image light on a screen 9.
[0052]
As a result, the subfield image receives a predetermined amount of displacement, and the image displayed by the reflective spatial light modulator 6 to the observer without actually multiplying the number of pixels of the reflective spatial light modulator 6. An image having a resolution four times that of the above can be displayed, and a high-definition image can be displayed.
[0053]
The irradiation light that has not been spatially modulated by the reflective spatial light modulator 6 is transmitted through the polarizing beam splitter and returned to the light source.
[0054]
By the way, in the display device 1 of the present embodiment, the polarization dependent lens array 5 is provided between the reflection type spatial light modulator 6 and the polarization beam splitter 4. As described above, the polarization-dependent lens array 5 separates the irradiation light irradiated from the polarization beam splitter 4 side and the image light (image light) reflected from the reflective spatial light modulator 6 from each other. It has different polarization dependence. As described above, the polarization-dependent lens array 5 of the present embodiment differs from the single polarization-dependent lens array 5 in that the radius of curvature for the irradiation light and the radius of curvature for the image light differ from each other. The lens power for the image light is set to be larger than the power.
[0055]
Here, FIG. 2 is a perspective view showing a part of the display device 1. As shown in FIG. 2, the polarization-dependent lens array 5 has an optical axis (an axis of optical anisotropy) in a direction indicated by an arrow A. In FIG. 2, when the refractive index for polarized light parallel to the direction indicated by arrow A is ne, and the refractive index for polarized light perpendicular to the direction indicated by arrow A (arrow B in FIG. 2) is no, the light transmitted through the polarization beam splitter 4. The polarization direction of the irradiation light is orthogonal to the optical axis direction A of the polarization dependent lens array 5, and its refractive index is no.
[0056]
When the pixels in the reflective spatial light modulator 6 are in a bright state, the polarization direction of the light reflected as image light is parallel to the optical axis of the polarization dependent lens array 5, and the polarization dependent lens array 5 Has a refractive index of ne. Here, assuming that the radius of curvature of the polarization dependent lens array 5 is r, the focal length of the polarization dependent lens array 5 is represented by the following equations (1) and (2).
Focal length for irradiation light: f = r / (no-1) (1)
Focal length for image light: f = r / (ne-1) (2)
[0057]
According to the equations (1) and (2), the focal length of the polarization dependent lens array 5 for the irradiation light (outgoing path) and the projection light (return path) can be changed, that is, the lens power can be changed.
[0058]
By using such a polarization-dependent lens array 5, in the display device of the present embodiment, the optical path between the irradiation light and the image light is made different despite the use of the reflective spatial light modulator 6. Even if the optical path is shifted by driving the pixel shift element 7, the bleeding between adjacent pixels on the screen 9 can be suppressed, so that the display image can be made higher definition. The degree of freedom in designing the polarization dependent lens array 5 can be increased.
[0059]
In the present embodiment, the reflection type spatial light modulator 6 is formed of one liquid crystal, but is not limited to this. For example, the polarization dependent lens array 5 and the reflection type spatial light modulator may be used. 6 may be stacked, and a color separation element may be arranged between the polarization dependent lens array 5 and the reflective spatial light modulator 6 in each set. Thus, a color image can be displayed on the screen.
[0060]
In the present embodiment, the polarization beam splitter 4 transmits light polarized in the vertical direction in FIG. 1 and reflects light polarized in the front and back directions in FIG. 1. However, the present invention is not limited to this. 1. A polarizing beam splitter that reflects light polarized in the vertical direction of the paper surface of FIG. 1 and transmits light polarized in the front and back directions of the paper surface of FIG. However, when such a polarization beam splitter is used, the polarization dependence of the polarization-dependent lens array 5 is reversed from the polarization dependence shown in FIG.
[0061]
In addition, in the present embodiment, at the time of displaying an image, the image of a single display frame displayed by the reflective spatial light modulator 6 is shifted to a plurality of positions by a pixel shift element, thereby improving the definition of the displayed image. However, the display method is not limited to this. For example, a single display frame image displayed by the reflective spatial light modulator 6 is configured by a plurality of time-divided subframes, The spatial light modulation of the irradiation light by the reflective spatial light modulator 6 is performed for each sub-frame, and the image of the single display frame is displayed by operating the pixel shift element 7 in synchronization with the switching of the sub-frame. By doing so, the definition of the display image may be improved.
[0062]
At this time, the number of divisions of the display frame is preferably 2 or more, and the upper limit depends on the display frame period, the scanning time required for updating the image in the reflective spatial light modulator 6, the number of divisions of the display frame, and the like. Is set.
[0063]
Next, a second embodiment of the present invention will be described with reference to FIG. Note that the same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. The same applies hereinafter.
[0064]
FIG. 3 is a schematic diagram showing a display device according to the second embodiment of the present invention. As shown in FIG. 3, in the display device 20 of the present embodiment, the arrangement state of the polarization dependent lens array 21 and the reflective spatial light modulator 22 between the polarization beam splitter 4 and the pixel shift element 7 is as follows. This is different from the above embodiment.
[0065]
In the display device 20 of the present embodiment, a polarization-dependent lens array 21 as a polarization-dependent member and a reflective spatial light modulator 22 are arranged in contact with each other.
[0066]
As described above, the lens power in the polarization-dependent lens array 21 of the present embodiment is different between the irradiation light and the image light, and the lens power for the image light is larger than the lens power for the irradiation light. Is set to
[0067]
The reflective spatial light modulator 22 includes a liquid crystal 23 and a silicon back plane 24 including a reflective electrode (not shown). The liquid crystal 23 in the reflective spatial light modulator 22 of the present embodiment is sandwiched between the silicon back plane 24 and the polarization dependent lens array 21.
[0068]
In the display device having such a configuration, since the polarization-dependent lens array 21 is disposed in contact with the liquid crystal 23 of the reflective spatial light modulator 22, the image light spatially modulated by the reflective spatial light modulator 22 is provided. Can be respectively incident on the lens corresponding to the pixel that generated each image light. Thereby, when the image light is spatially modulated by the reflection type spatial light modulator 22 and enters the corresponding lens in the polarization dependent lens array 21, the image light enters another lens adjacent to this lens. Can be reduced.
[0069]
As a result, the light use efficiency can be improved, and the display image can be made higher definition.
[0070]
Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 4 is a schematic diagram showing a display device according to the third embodiment of the present invention. As shown in FIG. 4, in the display device 30 of the present embodiment, the arrangement state of the polarization dependent lens array 31 and the reflection type spatial light modulator 32 between the polarization beam splitter 4 and the pixel shift element 7 is as follows. This is different from the above embodiment.
[0071]
The polarization-dependent lens array 31 according to the present embodiment includes a lens array substrate 33 in which a plurality of lenses having polarization dependence are arranged in an array, and a plate-shaped parallel lens opposed to the lens array substrate 33 in parallel. It has a flat plate 34 and a uniaxial optically anisotropic material 35 sandwiched between the lens array substrate 33 and the parallel flat plate 34. In the present embodiment, a polarization dependent member is realized by the polarization dependent lens array 31, and an optically transparent flat plate is realized by the parallel flat plate 34.
[0072]
The lens array substrate 33 and the parallel plate 34 need not be optically anisotropic. The lens array substrate 33 and the parallel flat plate 34 can be formed of, for example, synthetic quartz or optical glass.
[0073]
The reflection type spatial light modulator 32 is the same as the reflection type spatial light modulator 6 of the first embodiment.
[0074]
As described above, by forming the polarization dependent lens array 31 in which the uniaxial optically anisotropic material 35 is sandwiched between the lens array substrate 33 and the parallel plate 34, the uniaxial optically anisotropic material 35 is directly The lens power for the irradiation light and the projection light can be changed without performing lens array processing, and the polarization-dependent lens array 31 can be easily manufactured.
[0075]
In the present embodiment, as shown in FIG. 4, the lens array substrate 33 is disposed on the polarization beam splitter 4 side. However, the present invention is not limited to this. The parallel plate 34 may be arranged on the side of the polarization beam splitter 4.
[0076]
Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 5 is a schematic diagram illustrating a display device according to a fourth embodiment of the present invention. As shown in FIG. 5, in the display device 40 of the present embodiment, the arrangement state of the polarization dependent lens array 41 and the reflective spatial light modulator 42 between the polarization beam splitter 4 and the pixel shift element 7 is as follows. This is different from the above embodiment.
[0077]
The polarization-dependent lens array 41 of the present embodiment has two lens array substrates 43 and 44 and a uniaxial anisotropic material 45 sandwiched between the lens array substrates 43 and 44. In the present embodiment, a polarization dependent member is realized by the polarization dependent lens array 41.
[0078]
The lens array substrates 43 and 44 do not need to be optically anisotropic, and can be formed of, for example, synthetic quartz or optical glass.
[0079]
Further, the reflective spatial light modulator 42 is the same as the reflective spatial light modulator 6 of the first embodiment.
[0080]
In the display device 40 having such a configuration, the lens power of each of the lens array substrates 43 and 44 included in the polarization-dependent lens array 41 can be adjusted for each of the lens array substrates 43 and 44. The degree of freedom in designing the dependency lens array 41 can be improved.
[0081]
In this embodiment, as shown in FIG. 5, the shape of each of the lens array substrates 43 and 44 is a convex lens array shape. However, the shapes of the lens array substrates 43 and 44 are not limited thereto. One or both of the lens array substrates 43 and 44 may have a concave lens array shape.
[0082]
Next, a fifth embodiment of the present invention will be described with reference to FIG. FIG. 6 is a schematic diagram illustrating a display device according to a fifth embodiment of the present invention. As shown in FIG. 6, in the display device 50 of the present embodiment, the arrangement state of the polarization dependent lens array 51 and the reflection type spatial light modulator 52 between the polarization beam splitter 4 and the pixel shift element 7 is as follows. This is different from the above embodiment.
[0083]
The polarization-dependent lens array 51 of the present embodiment includes a lens array substrate 53 in which a plurality of polarization-dependent lenses are arranged in an array, and a plate-shaped parallel plate opposing the lens array substrate 53 in parallel. It has a flat plate 54 and a uniaxial optically anisotropic material 55 filled between the lens array substrate 53 and the parallel flat plate 54. In the present embodiment, a polarization dependent member is realized by the polarization dependent lens array 51, and an optically transparent flat plate is realized by the parallel flat plate 54.
[0084]
The lens array substrate 53 is configured by arranging a plurality of convex lens-shaped lenses in an array. Assuming that the extraordinary light refractive index of the uniaxial anisotropic material 55 is ne, the refractive index of the lens array substrate 53 is set substantially equal to the extraordinary light refractive index ne of the uniaxial anisotropic material 55. The refractive index of the parallel plate 54 can be set arbitrarily.
[0085]
The uniaxial anisotropic material 55 has an optical axis parallel to the vibration direction of the irradiation light (p-polarized light) transmitted through the polarization beam splitter 4. This optical axis is parallel to the plane direction of the parallel flat plate 54, and is the vertical direction in FIG.
[0086]
The reflective spatial light modulator 52 includes a lens array in which lenses (not shown) for reducing the size of the pixels are arranged in an array corresponding to each pixel.
[0087]
In the display device 50 having such a configuration, since the refractive indexes of the lens array substrate 53 and the uniaxial anisotropic material 55 are set substantially equal, the irradiation light transmitted through the polarization beam splitter 4 Irradiated toward the reflection type spatial light modulator 52 without being affected. This irradiation light is reflected by the reflection type spatial light modulator 52 as image light after its polarization state is rotated by 90 °.
[0088]
For this reason, the image light reflected by the reflective spatial light modulator 52 and re-entering the uniaxial anisotropic material 55 feels the refractive index of the uniaxial anisotropic material 55 as ordinary light refractive index no, and refracts the lens array substrate. I feel the rate is almost ne. As a result, a refractive index difference of almost (ne-no) occurs, and a lens effect can be exerted by the refractive index difference.
[0089]
That is, according to the polarization dependent lens array 51 of the present embodiment, the lens function can be exerted on the image light without exerting the lens function on the irradiation light.
[0090]
Accordingly, the operation using the transmission-type spatial light modulator and the lens array can be realized despite the optical system that uses the lens array for the reflection-type spatial light modulator 52 to reduce the size of the pixel. That is, by reducing the size of each pixel by a lens (not shown) corresponding to each pixel, it is possible to more effectively realize high definition of a display image achieved.
[0091]
In addition, since the lens effect can be exerted only on the image light, the light use efficiency is not reduced, and the use of the pixel shift element 7 together with the shift of the image light further enhances the definition of the displayed image. Can be achieved.
[0092]
In FIG. 6, the lens array substrate 53 of the polarization dependent lens array 51 has a convex lens shape. However, the present invention is not limited to this. For example, as in the display device 50 ′ shown in FIG. The lens array substrate 53 'may have a concave lens shape. At this time, the refractive index of the concave lens-shaped lens array substrate 53 ′ is set substantially equal to the ordinary light refractive index no of the uniaxial anisotropic material 55. Also, in the display device 50 'shown in FIG. 7, the refractive index of the parallel plate 54 can be set to an arbitrary value. In addition, the optical axis of the uniaxial anisotropic material 55 in the display device 50 'is set in the vertical direction on the paper of FIG.
[0093]
In the display device 50 ′ having such a configuration, the irradiation light transmitted through the polarization beam splitter 4 has substantially the same refractive index no of the lens array substrate 53 ′ formed in a concave shape and the uniaxial anisotropic material 55. Since the user feels it, it goes to the reflective spatial light modulator 52 without being affected by the lens function, is spatially modulated by the reflective spatial light modulator 52, and is reflected as image light.
[0094]
The polarization direction of the image light spatially modulated by the reflective spatial light modulator 52 is rotated by 90 ° with respect to the incident light, so that the refractive index ne of the uniaxial anisotropic material 55 and the lens array substrate 53 ′. Of the lens array substrate 53 ', the lens functions as a lens.
[0095]
Accordingly, the operation using the transmission-type spatial light modulator and the lens array can be realized despite the optical system that uses the lens array for the reflection-type spatial light modulator 52 to reduce the size of the pixel. That is, by reducing the size of each pixel by a lens (not shown) corresponding to each pixel, it is possible to more effectively realize high definition of a display image achieved.
[0096]
In the present embodiment, in the polarization-dependent lens array 51 or 51 ′ in the display device described with reference to FIGS. 6 and 7, the following expressions (3) and (4) or (5) are used. And, the state where the expression (6) is satisfied is a state where the refractive index of the lens array substrate 53 or 53 ′ becomes substantially equal to the ordinary light refractive index / the extraordinary light refractive index of the uniaxial anisotropic material 55.
[0097]
That is, assuming that the refractive index of the substrate is N, the fact that this refractive index N is substantially equal to the ordinary light refractive index no means that the following expression (3) is satisfied.
| N-no | <| ne-no | (3)
[0098]
The fact that the refractive index N is substantially equal to the ordinary light refractive index no more preferably satisfies the following expression (4).
[0099]
| N-no | <0.1 × | ne-no | (4)
[0100]
Similarly, the fact that the refractive index N is substantially equal to the extraordinary light refractive index ne indicates that the following expression (5) is satisfied.
| N-ne | <| ne-no | (5)
[0101]
The fact that the refractive index N is substantially equal to the extraordinary light refractive index ne more preferably satisfies the following expression (6).
| N-ne | <0.1 × | ne-no | (6)
[0102]
Next, a sixth embodiment of the present invention will be described with reference to FIG. FIG. 8 is a schematic diagram showing a display device according to the sixth embodiment of the present invention. As shown in FIG. 8, in the display device 60 of the present embodiment, the arrangement state of the polarization dependent lens array 61 and the reflection type spatial light modulator 62 between the polarization beam splitter 4 and the pixel shift element 7 is as follows. This is different from the above embodiment.
[0103]
The polarization-dependent lens array 61 in the display device of the present embodiment includes two lens array substrates 63 and 64 and a uniaxial anisotropic material 65 filled between the lens array substrates 63 and 64. are doing. Each of the lens array substrates 63 and 64 is configured by arranging a plurality of lenses having a convex lens shape in an array, and a structure in which a uniaxial anisotropic material 65 is filled between the lens surfaces with the respective lens surfaces facing each other. have. In the present embodiment, a polarization dependent member is realized by the polarization dependent lens array 61.
[0104]
The polarization-dependent lens array 61 of the present embodiment does not have a lens function for irradiation light at the interface between the lens array substrates 63 and 64 and the uniaxial anisotropic material 65, and exhibits a lens function for image light.
[0105]
Here, assuming that the ordinary light refractive index no of the uniaxial anisotropic material 65 and the extraordinary refractive index ne of the uniaxial anisotropic material 65, at least one of the refractive indices of the lens array substrates 63 and 64 is the uniaxial anisotropic material. It is set substantially equal to the extraordinary light refractive index ne of 65. Note that the definition of "substantially equal" is the same as described above.
[0106]
The optical axis of the uniaxially anisotropic material 65 is set in a vertical direction on the paper of FIG. 8 and perpendicular to the illumination light.
[0107]
In the display device 60 having such a configuration, the refractive index of at least one of the lens array substrates 63 and 64 in the polarization dependent lens array 61 is set equal to the extraordinary light refractive index ne of the uniaxial anisotropic material 65. The polarization-dependent lens array 61 can change the power of the lens that acts on the irradiation light and the image light.
[0108]
Although not particularly shown, by setting both the refractive indexes of the lens array substrates 63 and 64 to be substantially the same as the extraordinary light refractive index ne, the polarization-dependent lens array 61 does not exhibit a lens function for irradiation light. In addition, the lens function can be exhibited only for image light.
[0109]
With such a configuration, for example, as described in the above-described fifth embodiment, when the polarization-dependent lens arrays 51 and 51 ′ using the lens array substrates 53 and 53 ′ and the parallel flat plate 54 are used. As compared with the above, the lens function can be exerted only on the image light, and the lens power exerted on the image light can be increased.
[0110]
Next, a seventh embodiment of the present invention will be described with reference to FIG. FIG. 9 is a schematic diagram showing a display device according to the seventh embodiment of the present invention. As shown in FIG. 9, in the display device 70 of the present embodiment, the arrangement state of the polarization dependent lens array 71 and the reflection type spatial light modulator 72 between the polarization beam splitter 4 and the pixel shift element 7 is as follows. This is different from the above embodiment.
[0111]
The polarization-dependent lens array 71 in the display device 70 of the present embodiment has two lens array substrates 73 and 74 and a uniaxial anisotropic material 75 filled between the lens array substrates 73 and 74. ing. In the present embodiment, a polarization dependent member is realized by the polarization dependent lens array 71.
[0112]
Each of the lens array substrates 73 and 74 has a configuration in which a plurality of concave lenses are arranged in an array. The refractive index of at least one of the two lens array substrates 73 and 74 is set substantially equal to the ordinary refractive index no of the uniaxial anisotropic material 75. Note that the definition of "substantially equal" is the same as described above.
[0113]
The optical axis of the uniaxial anisotropic material 75 is set in the up-down direction in FIG.
[0114]
According to such a configuration, the at least one lens array substrate 73 or 74 and the uniaxial anisotropic material 75 do not exert a lens effect on irradiation light, but exhibit a convex lens effect only on image light. It is possible to change the lens power between the irradiation light and the projection light.
[0115]
Next, an eighth embodiment of the present invention will be described with reference to FIG. FIG. 10 is a schematic diagram showing a display device according to the eighth embodiment of the present invention. As shown in FIG. 10, in the display device 80 of the present embodiment, the arrangement state of the polarization dependent lens array 81 and the reflective spatial light modulator 82 between the polarization beam splitter 4 and the pixel shift element 7 is as follows. This is different from the above embodiment.
[0116]
As shown in FIG. 10, the polarization-dependent lens array 81 includes a lens array substrate 83 and a parallel plate 84, and a liquid crystal 85 as a uniaxial anisotropic material filled between the lens array substrate 83 and the parallel plate 84. It is constituted by. In the present embodiment, a polarization dependent member is realized by the polarization dependent lens array 81, and an optically transparent flat plate is realized by the parallel flat plate 84. In the present embodiment, a pair of optically transparent substrates is realized by the lens array substrate 83 and the parallel flat plate 84.
[0117]
The liquid crystal 85 is homogeneously oriented between the lens array substrate 83 and the parallel plate 84.
[0118]
Incidentally, the orientation direction of the liquid crystal molecules in the liquid crystal 85 as a uniaxial anisotropic material filled between the lens array substrate 83 and the parallel plate 84, and the refractive index of the liquid crystal 85 and the refractive index of the lens array substrate 83 and the parallel plate 84. A plurality of combinations of the refractive indexes can be set. The ordinary light refractive index of the liquid crystal 85 is no, and the extraordinary light refractive index is ne.
[0119]
Here, for example, a configuration is conceivable in which the refractive index of the lens array substrate 83 is substantially ne, the orientation direction of the liquid crystal molecules in the liquid crystal 85 is parallel to the paper of FIG. 10, and the refractive index of the parallel flat plate 84 is arbitrary. In such a configuration, the lens array substrate 83 does not exert the lens effect on the irradiation light, and exerts the lens effect only on the image light spatially modulated by the reflective spatial light modulator 82. It is possible.
[0120]
Further, for example, the lens array substrate 83 is a lens array substrate (not shown) having a concave lens shape, the refractive index of the lens array substrate having the concave lens shape is made substantially equal to the ordinary light refractive index no of the liquid crystal 85, and Can be considered as a direction in which the orientation direction of FIG. In such a configuration, the lens effect is not exerted on the irradiation light, but the lens effect can be exerted only on the spatial light modulated image light.
[0121]
In any case, as in the present embodiment, by using the liquid crystal 85 as the uniaxial anisotropic material, the liquid crystal 85 is filled between the lens array substrate 83 and the parallel flat plate 84 without any gap. Since it is possible to give the uniaxial anisotropy over the whole between the 83 and the parallel plate 84, the lens effect is exerted only on the image light without exerting the lens effect on the irradiation light. The polarization-dependent lens array 81 that can be manufactured can be easily manufactured as compared with a case where a solid uniaxial anisotropic material is processed.
[0122]
Next, a ninth embodiment of the present invention will be described with reference to FIG. FIG. 11 is a schematic diagram showing a display device according to the ninth embodiment of the present invention. As shown in FIG. 11, in the display device 90 of the present embodiment, the arrangement state of the polarization dependent lens array 91 and the reflection type spatial light modulator 92 between the polarization beam splitter 4 and the pixel shift element 7 is as follows. Unlike the above embodiment, the polarization dependent lens array 91 and the reflection type spatial light modulator 92 are integrated.
[0123]
The polarization dependent lens array 91 includes a lens array substrate 93, a parallel plate 94, and a liquid crystal 95 as a uniaxial anisotropic material filled between the lens array substrate 93 and the parallel plate 94. In the present embodiment, a polarization dependent member is realized by the polarization dependent lens array 91, and an optically transparent flat plate is realized by the parallel flat plate 94. In the present embodiment, a pair of optically transparent substrates is realized by the lens array substrate 93 and the parallel flat plate 94. A plurality of combinations of the refractive index of the lens array substrate 93 and the parallel plate 94, the refractive index of the liquid crystal 95, and the orientation direction of the liquid crystal can be given as described above. The ordinary light refractive index of the liquid crystal 95 is set to no, and the extraordinary light refractive index is set to ne.
[0124]
The reflection type spatial light modulator 92 includes a silicon back plane 96 including a pixel reflection electrode, a parallel flat plate 94, and a liquid crystal 97 sandwiched between the silicon back plane 96 and the parallel flat plate 94. That is, in the present embodiment, the parallel flat plate 94 is used for both holding the liquid crystal 95 in the polarization dependent lens array 91 and holding the liquid crystal 97 in the reflective spatial light modulator 92. By reducing the number of substrates to be formed and by integrating the components, the size of components can be reduced and the size of the device can be reduced.
[0125]
Further, by integrating the polarization dependent lens array 91 and the reflective spatial light modulator 92 via the parallel flat plate 94, the spatial light is modulated by the reflective spatial light modulator 92 and It is possible to prevent the image light incident on the pixel 91 from being incident on the adjacent lens in addition to the corresponding lens, and to improve the light use efficiency. Thereby, the definition of the image displayed on the screen 9 can be improved.
[0126]
Here, when the polarization-dependent lens array 91 exerts a convex lens power on image light, the polarization direction of light passing through the polarization beam splitter 4 and entering the polarization-dependent lens array 91 is determined by the polarization-dependent lens. The relationship between the lens shape in the array 91 and the refractive index of the polarization-dependent lens array 91 is set as follows. That is, when the lens array substrate 93 has a convex lens shape, the refractive index of the lens array substrate 93 is set to be equal to the extraordinary light refractive index of the liquid crystal 95 which is a uniaxial anisotropic material, and is transmitted through the polarization beam splitter 4 to be polarization dependent. The direction of deflection of light incident on the chromatic lens array 91 is set equal to the extraordinary light refractive index of the liquid crystal 95. Thereby, it is possible to realize the polarization-dependent lens array 91 that exerts the convex lens power on the image light.
[0127]
When the lens array substrate 93 has a concave lens shape in the polarization-dependent lens array 91, the refractive index of the lens array substrate 93 is set equal to the ordinary refractive index of the liquid crystal 95 which is a uniaxial anisotropic material, and the polarization beam splitter is set. The polarization-dependent lens array 91 that exerts a convex lens power on image light is realized by setting the direction of deflection of light that passes through 4 and enters the polarization-dependent lens array 91 equal to the ordinary refractive index of the liquid crystal 95. can do.
[0128]
Further, the polarization direction of the light that passes through the polarization beam splitter 4 and enters the polarization-dependent lens array 91 is parallel to the optical axis of the uniaxial anisotropic material, and the refractive index of the lens array substrate 93 is made of the uniaxial anisotropic material. By setting the refractive index equal to the extraordinary light refractive index of a certain liquid crystal 95, a polarization-dependent lens array 91 that exerts a convex lens power on image light can be realized.
[0129]
Further, the polarization direction of the light that passes through the polarization beam splitter 4 and enters the polarization-dependent lens array 91 is perpendicular (orthogonal) to the optical axis of the uniaxial anisotropic material, and the refractive index of the lens array substrate 93 is uniaxially different. By setting the refractive index equal to the ordinary light refractive index of the liquid crystal 95, which is an isotropic material, it is possible to realize a polarization-dependent lens array 91 that exerts a convex lens power on image light.
[0130]
Next, a tenth embodiment of the present invention will be described with reference to FIGS. FIG. 12 is a schematic diagram showing a display device according to the tenth embodiment of the present invention. As shown in FIG. 12, in the display device 100 of the present embodiment, the arrangement state of the polarization dependent lens array 101 and the reflection type spatial light modulator 102 between the polarization beam splitter 4 and the pixel shift element 7 is as follows. This is different from the above embodiment.
[0131]
The polarization-dependent lens array 101 includes a lens array substrate 103, a parallel plate 104, and a liquid crystal 105 sandwiched between the lens array substrate 103 and the parallel plate 104. In the present embodiment, a polarization dependent member is realized by the polarization dependent lens array 101, and an optically transparent flat plate is realized by the parallel flat plate 104. In the present embodiment, a pair of optically transparent substrates is realized by the lens array substrate 103 and the parallel flat plate 104.
[0132]
The liquid crystal molecules 105 a (see FIG. 13) in the liquid crystal 105 are oriented such that the major axis direction is parallel to the parallel flat plate 104. The long axis direction of the liquid crystal molecules 105a is oriented so as to be parallel to the paper surface. The ordinary light refractive index of the liquid crystal 95 is set to no, and the extraordinary light refractive index is set to ne.
[0133]
The refractive index of the lens array substrate 103 is set such that the ordinary light refractive index of the liquid crystal 95 is substantially equal to no. The dielectric constant of the lens array substrate 103 is set so that the difference from the dielectric constant of the liquid crystal 105 is as small as possible.
[0134]
On the lens array substrate 103 of the present embodiment, a transparent electrode 106 is provided on one surface side on which a lens is not formed.
[0135]
The transparent electrode 107 is provided on the surface of the parallel plate 104 on the lens array substrate 103 side.
[0136]
In addition, the display device 100 includes voltage applying means 108 for applying a voltage between the transparent electrode 106 provided on the lens array substrate 103 and the transparent electrode 107 provided on the parallel flat plate 104. The voltage applying means 108 can be realized by, for example, an AC power supply or the like. A control system (not shown) included in the display device 100 adjusts a voltage value applied between the transparent electrodes 106 and 107 by the voltage applying unit 108. Here, a voltage adjusting means is realized.
[0137]
In such a display device 100, when a voltage is applied between the transparent electrodes 106 and 107 by the voltage applying means 108, if the applied voltage is sufficiently small, as shown in FIG. The orientation state is maintained as it is in the initial state.
[0138]
When the voltage application unit 108 increases the voltage for applying a voltage between the transparent electrodes 106 and 107 by the control of the control system, the liquid crystal molecules 105a change according to the applied voltage as shown in FIG. As described above, while the major axis direction is parallel to the paper surface, it starts to tilt so as to rotate in the paper surface.
[0139]
Here, when the liquid crystal molecules 105a are in the state shown in FIG. 13A, the irradiation light does not feel the difference in the refractive index between the lens array substrate 103 and the liquid crystal 105, so that the light is polarized without receiving the lens effect. The light passes through the dependency lens array 101.
[0140]
The image light generated by the spatial light modulation of the irradiation light by the reflective spatial light modulator 102 has its deflection direction rotated by 90 ° with respect to the irradiation light. The lens effect is caused by the rate difference and the curved surface of the lens.
[0141]
When the liquid crystal molecules 105a are in the state shown in FIG. 13B, the difference in the refractive index is smaller than that in the case of FIG. For this reason, the lens power exerted on the image light is reduced, and the lens effect received by the image light spatially modulated by the reflective spatial light modulator 102 is reduced.
[0142]
That is, as in the present embodiment, the transparent electrodes 106 and 107 are provided on the lens array substrate 103 and the parallel flat plate 104 sandwiching the liquid crystal 105, respectively, and the voltage applied between the transparent electrodes 106 and 107 is adjusted. Thus, the lens effect received by the image light spatially modulated by the reflective spatial light modulator 102 can be varied.
[0143]
By the way, since the orientation distribution of the irradiation light emitted from the light source unit 2 varies, and the display device 100 is assembled with variations, as a result, the projection performance of the irradiation light, the light use efficiency, and the like vary. Sometimes.
[0144]
On the other hand, in the display device 100 of the present embodiment, since the lens power of the polarization-dependent lens array 101 can be adjusted by adjusting the voltage applied between the transparent electrodes 106 and 107, the irradiation light is projected. Variations in performance and light use efficiency can be suppressed.
[0145]
【The invention's effect】
According to the display device of the first aspect of the present invention, a light source for irradiating irradiation light, and a reflective spatial light modulator for reflecting image light obtained by spatially modulating the irradiation light irradiated by the light source using a plurality of pixels. Display control means for switching and displaying an image in units of sub-frames obtained by dividing a display frame into a plurality of display frames with respect to the reflective spatial light modulator; irradiation light emitted from the light source; and the reflective spatial light modulator A polarizing beam splitter for polarizing and separating the image light subjected to the spatial light modulation, a light path shifting means for shifting the image light separated by the polarizing light separating element in accordance with the switching of the display by the display control means, and after the light path shift. A magnifying optical system for magnifying and projecting the image light onto the object to be irradiated, and provided between the reflective spatial light modulator and the polarization beam splitting element, and having a different polarization dependency on the irradiation light and the image light. A polarization-dependent member having a reflection type spatial light modulator, the optical paths of the irradiation light and the image light partially overlap each other according to the polarization state thereof even when the optical paths partially overlap. Accordingly, it is possible to suppress bleeding between adjacent pixels in an image displayed by the display device using the reflective spatial light modulator, and to achieve higher definition of the display image.
[0146]
According to the second aspect of the present invention, in the display device according to the first aspect, the polarization-dependent member is associated with each pixel of the reflective spatial light modulator, and the polarization-dependent member is more than the lens power for the irradiation light. Since the lens has a lens whose power for the image light is set to be larger, the optical path between the irradiation light and the image light can be made different despite the use of the reflective spatial light modulator.
[0147]
According to the third aspect of the present invention, in the display device according to the second aspect, the polarization dependent member is formed of an optically transparent uniaxial anisotropic material. It is possible to easily produce a polarization-dependent member exhibiting the effect of (1).
[0148]
According to the fourth aspect of the present invention, in the display device according to the third aspect, the polarization-dependent member is configured such that lenses corresponding to respective pixels of the reflection-type spatial light modulator are arranged in an array, and the reflection-type member is arranged in the reflection-type spatial light modulator. Since it has a lens array substrate that is placed in contact with the spatial light modulator, the image light that has been spatially modulated by the reflective spatial light modulator surely enters the polarization dependent member, and the image light that has been spatially modulated by each pixel is It is possible to suppress the light from being incident on a lens adjacent to the corresponding lens, whereby the light use efficiency can be improved, and the display image can be made higher definition. In addition, by arranging the polarization dependent member and the reflective spatial light modulator in contact, the size of the device can be reduced.
[0149]
According to a fifth aspect of the present invention, in the display device according to the second aspect, the polarization-dependent member has a lens array substrate on which lenses corresponding to respective pixels of the reflective spatial light modulator are arranged in an array. 3. The invention according to claim 2, wherein the optical disk is constituted by an optically transparent flat plate facing the lens array substrate, and a uniaxial anisotropic material filled between the lens array substrate and the flat plate. Can easily produce a polarization-dependent lens array exhibiting the effect of (1).
[0150]
According to a sixth aspect of the present invention, in the display device of the fifth aspect, the uniaxial anisotropic material has an ordinary light refractive index or an extraordinary light refractive index equal to the refractive index of the lens array substrate. , And the lens power can be exerted only for the image light, so that the displayed image can be made higher definition.
[0151]
According to the seventh aspect of the present invention, in the display device according to the second aspect, the polarization dependent member includes a pair of lenses in which lenses corresponding to each pixel of the reflective spatial light modulator are arranged in an array. Since it is composed of the array substrate and the uniaxial anisotropic material filled between the lens array substrates, it is possible to improve the productivity of the polarization-dependent lens array exhibiting the effect of the second aspect of the present invention. .
[0152]
According to the invention described in claim 8, in the display device described in claim 7, the uniaxial anisotropic material has an ordinary light refractive index or an extraordinary light refractive index equal to the refractive index of at least one of the lens array substrates. The lens power for the irradiation light can be eliminated, and the lens power can be exerted only for the image light, so that the displayed image can be made higher definition.
[0153]
According to a ninth aspect of the present invention, in the display device according to any one of the fourth to seventh aspects, the uniaxial anisotropic material is a liquid crystal filled between a pair of optically transparent substrates. Therefore, the liquid crystal can be filled without gaps between the substrates sandwiching the liquid crystal, so that the polarization-dependent lens array is not increased in size, and compared with a case where a uniaxial anisotropic material in a crystalline state is used. This eliminates the need for processing the uniaxial anisotropic material itself into a lens array structure.
[0154]
According to a tenth aspect of the present invention, in the display device according to the ninth aspect, an electrode provided on each of the substrates of the polarization-dependent member, and a voltage applying unit configured to apply a voltage to the electrode, And a voltage adjusting means for adjusting a voltage value applied by the voltage applying means, the dispersion of the orientation distribution of the irradiation light emitted from the light source and the dispersion at the time of assembling the display device cause the projection performance of the irradiation light. Even if there is a variation in the light utilization efficiency, the lens power of the polarization-dependent lens array can be adjusted by adjusting the voltage applied to the electrodes, so that the projection performance of the irradiation light and the light utilization efficiency can be adjusted. Can be suppressed.
[0155]
According to an eleventh aspect of the present invention, in the display device according to the ninth or tenth aspect, the reflective spatial light modulator is configured to perform spatial light modulation by changing the orientation of a liquid crystal filled between a pair of optically transparent substrates. And the substrate in the polarization-dependent member also serves as the substrate supporting the liquid crystal in the reflection-type spatial light modulator, so that the image light spatially modulated by the reflection-type spatial light modulator surely has a polarization-dependent lens. In addition to the light being incident on the array, it is possible to suppress the light from being incident on the adjacent lens, and it is possible to improve the light use efficiency and achieve higher definition of the displayed image. Further, the size of the device can be reduced by using the substrate supporting the liquid crystal in the reflective spatial light modulator for the polarization dependent lens array.
[0156]
According to the twelfth aspect of the present invention, in the display device of the ninth or tenth aspect, the substrate in the polarization dependent member has a convex or concave lens shape, and a refractive index of the lens array substrate is a uniaxial anisotropic material. Since the refractive index is set equal to the extraordinary light refractive index or the ordinary light refractive index, it is possible to realize a polarization-dependent lens array that exerts a convex lens power on image light.
[0157]
According to a thirteenth aspect of the present invention, in the display device according to the ninth or tenth aspect, a polarization direction of light incident on the polarization dependent member from the polarization separation element is parallel to an optical axis of the uniaxial anisotropic material. Or, since the refractive index of the substrate is set to be equal to the extraordinary or ordinary light refractive index of the uniaxial anisotropic material, a polarization-dependent lens array that exerts a convex lens power on image light is realized. can do.
[Brief description of the drawings]
FIG. 1 is a schematic diagram illustrating an optical system configuration of an entire display device according to a first embodiment of the present invention.
FIG. 2 is a perspective view showing a part of the display device.
FIG. 3 is a schematic diagram illustrating a display device according to a second embodiment of the present invention.
FIG. 4 is a schematic diagram illustrating a display device according to a third embodiment of the present invention.
FIG. 5 is a schematic diagram showing a display device according to a fourth embodiment of the present invention.
FIG. 6 is a schematic diagram showing a display device according to a fifth embodiment of the present invention.
FIG. 7 is a schematic diagram showing a display device according to another embodiment of the present invention.
FIG. 8 is a schematic diagram showing a display device according to a sixth embodiment of the present invention.
FIG. 9 is a schematic diagram illustrating a display device according to a seventh embodiment of the present invention.
FIG. 10 is a schematic diagram showing a display device according to an eighth embodiment of the present invention.
FIG. 11 is a schematic view showing a display device according to a ninth embodiment of the present invention.
FIG. 12 is a schematic diagram showing a display device according to a tenth embodiment of the present invention.
FIG. 13 is an explanatory diagram showing a change in alignment of liquid crystal molecules due to application of a voltage.
[Explanation of symbols]
1 Display device
5 Polarization dependent lens array
6. Reflective spatial light modulator
4 Polarization separation element
7 Optical path shift means
8 Magnifying optical system
11 Light source
20 Display device
21 Polarization dependent lens array
24 reflection type spatial light modulator
30 Display device
31 Polarization Dependent Lens Array
32 reflective spatial light modulator
33 Lens array substrate
34 flat plate
40 Display device
41 Polarization Dependent Lens Array
42 reflective spatial light modulator
43,44 Lens array substrate
45 Uniaxial anisotropic material
50 Display device
51 Polarization-dependent lens array
52 reflective spatial light modulator
53 Lens array substrate
54 flat plates
55 Uniaxial anisotropic material
50 'display device
51 'polarization dependent lens array
53 'lens array substrate
60 Display device
61 Polarization Dependent Lens Array
62 reflective spatial light modulator
63, 64 lens array substrate
65 Uniaxial anisotropic material
70 Display device
71 Polarization Dependent Lens Array
72 reflective spatial light modulator
73, 74 Lens array substrate
75 Uniaxial anisotropic material, liquid crystal
80 Display device
81 Polarization Dependent Lens Array
82 reflective spatial light modulator
83 lens array substrate
83, 84 A pair of substrates
84 flat plates
85 Uniaxial anisotropic material, liquid crystal
90 Display device
91 Polarization Dependent Lens Array
92 reflective spatial light modulator
93 Lens array board
93,94 A pair of substrates
94 flat plate
95 Uniaxial anisotropic material, liquid crystal
100 display device
101 Polarization-dependent lens array
102 reflective spatial light modulator
103 Lens array substrate
103,104 A pair of substrates
104 flat plate
105 Uniaxial anisotropic material, liquid crystal
108 Voltage application means
106,107 electrodes

Claims (13)

A light source for irradiating irradiation light,
A reflective spatial light modulator that reflects image light obtained by spatially modulating the irradiation light irradiated by the light source using a plurality of pixels,
For the reflective spatial light modulator, display control means for switching and displaying an image in subframe units obtained by dividing the display frame into a plurality of frames,
A polarization separation element that performs polarization separation of irradiation light emitted from the light source and image light that has been spatially modulated by the reflective spatial light modulator,
Optical path shifting means for shifting the image light separated by the polarization splitting element in response to switching of display by the display control means,
An enlarging optical system for enlarging and projecting the image light after the optical path shift onto the object to be irradiated,
A polarization dependent member that is provided between the reflective spatial light modulator and the polarization splitting element and has different polarization dependence on the irradiation light and the image light.
A display device comprising: 2. The polarization-dependent member has a lens associated with each pixel of the reflective spatial light modulator and having a lens power for the image light set higher than a lens power for the irradiation light. Display device. The display device according to claim 2, wherein the polarization dependent member is formed of an optically transparent uniaxial anisotropic material. 4. The polarization dependent member according to claim 3, wherein a lens corresponding to each pixel of the reflection type spatial light modulator is arranged in an array, and has a lens array substrate arranged in contact with the reflection type spatial light modulator. Display device. The polarization-dependent member includes a lens array substrate in which lenses corresponding to each pixel of the reflective spatial light modulator are arranged in an array, an optically transparent flat plate facing the lens array substrate, and the lens 3. The display device according to claim 2, wherein the display device is formed of a uniaxial anisotropic material filled between the array substrate and the flat plate. The display device according to claim 5, wherein the uniaxial anisotropic material has an ordinary light refractive index or an extraordinary light refractive index equal to the refractive index of the lens array substrate. The polarization-dependent member, a pair of lens array substrates in which lenses corresponding to each pixel of the reflective spatial light modulator are arranged in an array, and a uniaxial anisotropic material filled between the lens array substrates 3. The display device according to claim 2, comprising: The display device according to claim 7, wherein the uniaxial anisotropic material has an ordinary light refractive index or an extraordinary light refractive index equal to the refractive index of at least one of the lens array substrates. The display device according to claim 3, wherein the uniaxial anisotropic material is a liquid crystal filled between a pair of optically transparent substrates. An electrode provided on each of the substrates that the polarization-dependent member has,
Voltage applying means for applying a voltage to the electrode,
Voltage adjusting means for adjusting a voltage value applied by the voltage applying means,
The display device according to claim 9, further comprising: The reflective spatial light modulator performs spatial light modulation by changing the orientation of liquid crystal filled between a pair of optically transparent substrates,
The display device according to claim 9, wherein the substrate in the polarization-dependent member also functions as the substrate that supports liquid crystal in the reflective spatial light modulator. 11. The substrate according to claim 9, wherein the substrate in the polarization dependent member has a convex or concave lens shape, and a refractive index of the lens array substrate is set equal to an extraordinary refractive index or an ordinary refractive index of the uniaxial anisotropic material. Display device. The polarization direction of light incident on the polarization dependent member from the polarization splitting element is parallel or perpendicular to the optical axis of the uniaxial anisotropic material, and the refractive index of the substrate is the extraordinary refractive index of the uniaxial anisotropic material. 11. The display device according to claim 9, wherein the display device is set equal to the ordinary light refractive index.

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