Projection type video display

Abstract

There are provided a write light valve for generating image-writing light by modulating write light, a driver for writing images into the write light valve based on image data, read light valves for each color for generating respective color image lights by modulating each received color illumination light, an imaging lens group for guiding the image-writing light emitted from the write light valve to the respective read light valves, a dichroic cube for combining together color image lights emitted from the respective read light valves, a projection lens for projecting each color image light combined together. The imaging lens group has a distortion aberration which reduces or cancels out a distortion aberration of the projection lens.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an explanation view illustrating an optical system in a projection type video display according to a conventional projection type video display;

FIG. 2 is an explanation view illustrating an optical system in a projection type video display according to an embodiment of the present invention;

FIG. 3A is an explanation view showing a situation where a quadrangle shape image written into a write light valve is written into read light valves, and the written images by using light on these read light valves are projected on a screen;

FIG. 3B is an explanation view showing the same situation in a conventional projection type video display, for comparison purposes;

FIG. 4A is an explanation view showing a situation where written images by using light on read light valves are projected;

FIG. 4B is an explanation view showing the same situation in a conventional projection type video display, for comparison purposes;

FIG. 5 is an explanation view showing a configuration having an image formation optical system in the configuration of FIG. 2;

FIG. 6 is an explanation view showing another example of a configuration having an image formation optical system;

FIG. 7 is an explanation view showing another example of a configuration having an image formation optical system;

FIG. 8 is an explanation view illustrating a single-panel type projection type video display according to an embodiment of the present invention;

FIG. 9 is an explanation view illustrating an optical system in a single-panel type projection type video display according to another example of an embodiment of the present invention;

FIG. 10 is an explanation view illustrating an optical system in a single-panel type projection type video display according to another example of an embodiment of the present invention;

FIG. 11 is an explanation view illustrating an light source capable of using a projection type video display according to the present invention;

FIG. 12A is an explanation view showing a situation where quadrangle shape images written into a write light valve are written into read light valves, and each written image by using light on read light valves are projected on the same position on a screen;

FIG. 12B is an explanation view showing the same situation in a conventional projection type video display, for comparison purposes;

FIG. 13A is an explanation view showing a situation where written images using light on read light valves are projected on a screen;

FIG. 13B is an explanation view showing the same situation in a conventional projection type video display, for comparison purposes;

FIG. 14A is an explanation view showing a situation where a barrel shape image written into a write light valve is written into read light valves, and the written image (the barrel shape) using light is projected in a quadrangle shape on a screen;

FIG. 14B is an explanation view showing the same situation in a conventional projection type video display, for comparison purposes;

FIG. 15 is a perspective view illustrating a conventional lens shift device;

FIG. 16 is a view showing an embodiment of the present invention and an explanation view showing an optical path changing, in a simplified optical system, in a case where a write light valve is shifted;

FIG. 17 is a view showing an embodiment of the present invention and an explanation view showing an optical path changing, in a simplified optical system, in a case where an imaging lens group is shifted;

FIG. 18 is a view showing an embodiment of the present invention, and a perspective view showing a writing optical system;

FIG. 19A is a view showing an embodiment of the present invention and a cross-sectional view showing a shift device of a write light valve;

FIG. 19B is a front view thereof; and

FIG. 20 is a view showing an embodiment of the present invention and a perspective view showing writing optical system.

Claims

1. A projection type video display, comprising: a write light valve for generating image-writing light by modulating write light;a driver for writing images into the write light valve based on image data;read light valves for each color, in which an image is written by the image-writing light emitted from the write light valve, for generating respective color image lights by modulating each received color illumination light;a writing optical system for guiding the image-writing light emitted from the write light valve to the respective read light valves;means for combining together color image lights emitted from the respective read light valves; anda projection optical system for projecting each color image light combined together,wherein the writing optical system has a distortion aberration which reduces or cancels out a distortion aberration of the projection optical system.

2. The projection type video display according to claim 1, wherein a pincushion distortion occurs in the projection image projected through the projection optical system, and a barrel distortion occurs in the image-writing light in the writing optical system.

3. The projection type video display according to claim 1, wherein a barrel distortion occurs in the projection image projected through the projection optical system, and a pincushion distortion occurs in the image-writing light in the writing optical system.

4. A projection type video display, comprising: a write light valve for generating image-writing light by modulating write light;a driver for writing images into the write light valve based on image data;read light valves for each color, in which an image is written by the image-writing light emitted from the write light valve, for generating respective color image lights by modulating each received color illumination light;a writing optical system for guiding the image-writing light emitted from the write light valve to the respective read light valves;means for combining together color image lights emitted from the respective read light valves; anda projection optical system for projecting each color image light combined together,wherein sizes of written images on the respective read light valves are different from one another due to the write lights having different peak-wavelengths, with the result that a difference in size of each color projected image on a screen is reduced due to the occurrence of a chromatic aberration of magnification in the projection optical system.

5. The projection type video display according to claim 4, wherein on the condition that a peak-wavelength of each write light is denoted by λ1, λ2, λ3 (λ1>λ2>λ3) and a wavelength of each color illumination light is denoted by λ11, λ12, λ13 (λ1<λ12<λ13), an image writing using the write light with wavelength λ1 is performed when the color illumination light with wavelength λ11 is incident on the read light valve, an image writing using the write light with wavelength λ2 is performed when the color illumination light with wavelength λ12 is incident on the read light valve, and an image writing using the write light with wavelength λ3 is performed when the color illumination light with wavelength λ13 is incident on the read light valve.

6. The projection type video display according to claim 1 or 4, wherein the driver adjusts a position of the image for each color which is written into the write light valve based on a given position adjustment amount.

7. The projection type video display according to claim 1 or 4, wherein the driver adjusts the size of the image for each color which is written into the write light valve based on a given size adjustment amount.

8. The projection type video display according to claim 1 or 4, wherein there is provided a shift device for shifting the write light valve or the writing optical system up-and-down and/or right-and-left in a plane perpendicular to an optical axis of the image writing.

9. The projection type video display according to claim 1 or 4, wherein there is further provided a shift instruction operation portion which inputs a signal indicating a shift by an user operation, wherein the driver adjusts the position of the image for each color which is written into the write light valve based on the signal indicating the shift.

10. A projection type video display, comprising: a write light valve for generating image-writing light by modulating write light;a driver for writing images into the write light valve based on image data;a single read light valve, in which images are written by the image-writing lights emitted from the write light valve, for generating respective color image lights by modulating each received color illumination light;a writing optical system for guiding the image-writing light emitted from the write light valve to the read light valve; anda projection optical system for projecting the image light emitted from the read light valve,wherein the writing optical system has a distortion aberration which reduces or cancels out a distortion aberration of the projection optical system.

11. A projection type video display, comprising: a write light valve for generating image-writing light by modulating write light;a driver for writing images into the write light valve based on image data;a single read light valve, in which images are written by the image-writing lights emitted from the write light valve, for generating respective color image lights by modulating each received color illumination light;a writing optical system for guiding the image-writing light emitted from the write light valve to the read light valve; anda projection optical system for projecting the image light emitted from the read light valve,wherein the sizes of written images on the read light valve are different from one another due to the write light having different peak-wavelengths, with the result that a difference in size of each color projected image on a screen is reduced due to the occurrence of the chromatic aberration of magnification in the projection optical system.

12. The projection type video display according to claim 11, wherein on the condition that a peak-wavelength of each write light is denoted by λ1, λ2, λ3 (λ1>λ2>λ3) and a wavelength of each color illumination light is denoted by λ11, λ12, λ13 (λ11<λ2<λ13), an image writing using the write light with wavelength λ1 is performed when the color illumination light with wavelength λ11 is incident on the read light valve, an image writing using the write light with wavelength λ2 is performed when the color illumination light with wavelength λ12 is incident on the read light valve, and an image writing using the write light with wavelength λ3 is performed when the color illumination light with wavelength λ13 is incident on the read light valve.

13. The projection type video display according to claim 10 or 11, wherein there is further provided a polarization beam splitter and an optical member for introducing the image-writing light emitted from the write light valve to the read light valve and for introducing each color image light emitted from the read light valve to the projection optical system, wherein the write light is introduced into the write light valve after passing through the polarization beam splitter, and the image-writing light is changed into the particular polarized light, and the image-writing light is returned to the polarization beam splitter, and the returned image-writing light is reflected on the polarization beam splitter and is introduced into the optical member after passing through the writing optical system.

14. The projection type video display according to claim 10 or 11, wherein there is further provided an optical member for introducing the image-writing light emitted from the write light valve to the read light valve and for introducing each color image light emitted from the read light valve to the projection optical system, wherein the write light is introduced into the write light valve after passing through the optical member and the writing optical system, and the image-writing light is introduced into the read light valve after passing through the writing optical system and the optical member.

15. The projection type video display according to claim 10 or 11, wherein there is further provided an optical member for leading the image-writing light emitted from the write light valve to the read light valve and for leading each color image light emitted from the read light valve to the projection optical system, wherein the write light is introduced into the write light valve after passing through the optical member, and the image-writing light emitted from the write light valve introduced into the read light valve through the writing optical system after changing its optical path by the optical member, and each color image light is introduced into the projection optical system after passing through the writing optical system and the optical member, wherein an image formation plane of each color image light is formed between the projection optical system and the optical member.

16. The projection type video display according to claim 10 or 11, wherein there is provided a shift device for shifting the write light valve or the writing optical system up-and-down and/or right-and-left in a plane perpendicular to an optical axis of the image writing.

17. The projection type video display according to claim 10 or 11, wherein there is further provided a shift instruction operation portion which inputs a signal indicating a shift by an user operation, wherein the driver adjusts the position of the image for each color which is written into the write light valve based on the signal indicating the shift.