High efficiency electromagnetic beam projector, and systems and methods for implementation thereof

• US 6,034,818 A
• Filed: 05/10/1999
• Issued: 03/07/2000
• Est. Priority Date: 06/11/1992
• Status: Expired due to Term

• Current Assignee: Steven R. Sedlmayr
• Original Assignee: Steven R. Sedlmayr
• Inventors: Sedlmayr, Steven R.
• Primary Examiner(s): Schuberg, Darren E.
• Application Number:
  US09/309,394
• Time in Patent Office: 302 Days
• Field of Search: 359/489, 359/497, 359/502, 349/5, 349/8, 349/9, 353/20, 353/31, 353/34
• US Class Current: 359/283
• CPC Class Codes: G02B 26/02 for controlling the intensity of light G02B26/004 takes precedence
• CPC Class Codes: G02B 27/1006 for splitting or combining different wavelengths G02B27/1086, G02B27/141 take precedence
• CPC Class Codes: G02B 27/1046 for use with transmissive spatial light modulators
• CPC Class Codes: G02B 27/1053 having a single light modulator for all colour channels
• CPC Class Codes: G02B 27/1073 characterized by manufacturing or alignment methods
• CPC Class Codes: G02B 27/142 Coating structures, e.g. thin films multilayers
• CPC Class Codes: G02B 27/143 using macroscopically faceted or segmented reflective surfaces
• CPC Class Codes: G02B 27/144 using partially transparent surfaces without spectral selectivity G02B27/147 takes precedence
• CPC Class Codes: G02B 27/145 having sequential partially reflecting surfaces
• CPC Class Codes: G02B 27/149 using crossed beamsplitting surfaces, e.g. cross-dichroic cubes or X-cubes
• CPC Class Codes: G02B 27/283 used for beam splitting or combining
• CPC Class Codes: G03B 33/06 by additive-colour projection apparatus
• CPC Class Codes: G03B 35/26 using polarised or coloured light separating different viewpoint images
• CPC Class Codes: H04N 13/239 using two 2D image sensors having a relative position equal to or related to the interocular distance H04N13/243 takes precedence
• CPC Class Codes: H04N 13/334 using spectral multiplexing
• CPC Class Codes: H04N 13/337 using polarisation multiplexing
• CPC Class Codes: H04N 13/341 using temporal multiplexing
• CPC Class Codes: H04N 13/361 Reproducing mixed stereoscopic images; Reproducing mixed monoscopic and stereoscopic images, e.g. a stereoscopic image overlay window on a monoscopic image background
• CPC Class Codes: H04N 13/363 using image projection screens volumetric display H04N13/388
• CPC Class Codes: H04N 5/7441 the modulator being an array of liquid crystal cells
• CPC Class Codes: H04N 9/3105 : for displaying all colours simultaneously, e.g. by using two or more electronic spatial light modulators simultaneous projection in colour photography G03B33/10; beam splitting or combining systems per se G02B27/10
• CPC Class Codes: H04N 9/3152 : for shaping the light beam beam shaping per se G02B27/09
• CPC Class Codes: H04N 9/3167 : for polarizing the light beam polarizing optical systems per se G02B27/28
• CPC Class Codes: H04N 9/317 : Convergence or focusing systems electronic adjustment of convergence H04N9/3185; convergence or focusing arrangements for cathode ray tubes H04N9/28; means for automatic focusing of projectors not peculiar to the presence of an electronic spatial light modulator G03B21/53

Abstract

This invention relates to electromagnetic wave beam paths, formation of the beam, illumination of programmable electromagnetic wave field vector orientation rotating devices ("PEMFVORD") with an electromagnetic beam, and the technique of projection of the modulated beam. This invention also relates to a unique light path and method of forming the light into a rectangular beam to be used for optical projection systems and, more particularly, in a color and/or black and white liquid crystal device (LCD) projectors that produce high resolution, high brightness and/or three-dimensional images. This invention further relates to a device capable of receiving and displaying two-dimensional and three-dimensional images.

Claims

1. An optical projection system for modulating the intensity of an input beam of electromagnetic energy in response to a modulation signal having a first intensity component and a second intensity component wherein the input beam includes a first wavelength component and a different second wavelength component and wherein the first and second wavelength components each include an unspecified E vector polarization, the system comprising:

a. beam splitting apparatus for separating the input beam into first and second beam segments as a function of E vector polarization and not as a function of wavelength where the first beam segment includes a first substantially fixed E vector polarization and the second beam segment includes a second substantially fixed E vector polarization;

b. beam segment polarizing apparatus for rotating the E vector of the second beam segment to substantially align the E vector of the second beam segment to parallel the E vector of the first beam segment;

c. beam recombining apparatus for recombining the first and second beam segments into a substantially collimated, uniformly polarized beam having a defined cross sectional area and a single, substantially fixed E vector polarization;

d. filter apparatus for separating the uniformly polarized beam into a first wavelength beam element and a second wavelength beam element as a function of wavelength;

e. first variable polarizing apparatus for rotating the E vector polarization of the first wavelength beam element on a pixel by pixel basis as a function of the location of each discrete pixel element within the beam area and as a function of the first intensity component of the modulation signal to produce a first pixel rotated beam where each discrete pixel element includes an independently controlled, variable angle E vector polarization defined by the first intensity component of the modulation signal;

f. second variable polarizing apparatus for rotating the E vector polarization of the second wavelength beam element on a pixel by pixel basis as a function of the location of each discrete pixel element within the beam area and as a function of the second intensity component of the modulation signal to produce a second pixel rotated beam where each discrete pixel element includes an independently controlled, variable angle E vector polarization defined by the second intensity component of the modulation signal;

g. beam recombining apparatus for combining the first and second pixel rotated beams into a composite beam;

h. beam resolving apparatus for resolving the composite beam into collimated first and second output beams and for directing the first output beam in a first direction and the second output beam in a second direction angularly offset from the first direction, the first output beam having a substantially fixed first E vector polarization with discrete pixel elements independently varying in intensity as a direct function of both the first and second intensity components of the modulation signal and the second output beam having a substantially fixed second E vector polarization with discrete pixel elements independently varying in intensity as an inverse function of the first output beam; and

i. a lens for receiving the first output beam and for focusing the first output beam onto a target.

2. The optical projection system of claim 1 wherein the target includes a projection screen.

3. The system of claim 1 wherein the input beam comprises a light beam.

4. The system of claim 3 wherein the first intensity component of the modulation signal corresponds to a first color intensity signal and wherein the second intensity component of the modulation signal corresponds to a second color intensity signal.

5. The system of claim 3 wherein the beam splitting apparatus includes a polarizing beam splitter.

6. The system of claim 3 wherein the polarizing beam splitter includes a polarizing cube.

7. The system of claim 3 wherein the beam segment polarizing apparatus includes a half wave retarder.

8. The system of claim 3 wherein the first variable polarizing apparatus includes a first LCD and wherein the second variable polarizing apparatus includes a second LCD.

9. The system of claim 3 wherein the beam resolving apparatus includes a polarizing beam splitter.

10. The system of claim 9 wherein the polarizing beam splitter includes a polarizing cube.

11. The system of claims 1 or 3 wherein the first wavelength component includes a first band of wavelengths and wherein the second wavelength component includes a second band of wavelengths.

12. The system of claim 11 wherein the first and second bands of wavelengths are substantially non-overlapping.

13. The system of claims 1 or 3 wherein the first and second fixed E vector polarizations are substantially orthogonal.

14. A method for modulating the intensity of a light beam in response to a modulation signal having first, second and third intensity components wherein the light input beam includes first, second and third different wavelength components and for projecting the modulated light beam onto a target, comprising the steps of:

a. separating the input beam into first and second beam segments as a function of E vector polarization and not as a function of wavelength where the first beam segment includes a first substantially fixed E vector polarization and the second beam segment includes a second substantially fixed E vector polarization;

b. rotating the E vector of the second beam segment to substantially align the E vector of the second beam segment to parallel the E vector of the first beam segment;

c. recombining the first and second beam segments into a substantially collimated, uniformly polarized beam having a defined cross sectional area and a single, substantially fixed E vector polarization;

d. separating the uniformly polarized beam into a first, second and third wavelength beam elements as a function of wavelength;

e. rotating the E vector polarization of the first wavelength beam element on a pixel by pixel basis as a function of the location of each discrete pixel element within the beam area and as a function of the first intensity component of the modulation signal to produce a first pixel rotated beam where each discrete pixel element includes an independently controlled, variable angle E vector polarization defined by the first intensity component of the modulation signal;

f. rotating the E vector polarization of the second wavelength beam element on a pixel by pixel basis as a function of the location of each discrete pixel element within the beam area and as a function of the second intensity component of the modulation signal to produce a second pixel rotated beam where each discrete pixel element includes an independently controlled, variable angle E vector polarization defined by the second intensity component of the modulation signal;

g. rotating the E vector polarization of the third wavelength beam element on a pixel by pixel basis as a function of the location of each discrete pixel element within the beam area and as a function of the third intensity component of the modulation signal to produce a third pixel rotated beam where each discrete pixel element includes an independently controlled, variable angle E vector polarization defined by the third intensity component of the modulation signal;

h. combining the first, second and third pixel rotated beams into a composite beam;

i. resolving the composite beam into a collimated first output beam having a substantially fixed first E vector polarization with discrete pixel elements independently varying in intensity as a direct function of the first, second and third intensity components of the modulation signal and into a collimated second output beam having a substantially fixed second E vector polarization with discrete pixel elements independently varying in intensity as an inverse function of the first output beam;

j. directing the first output beam in a first direction and directing the second output beam in a second direction angularly offset from the first direction; and

k. intercepting the first output beam and focusing the first output beam onto the target.

15. The method of claim 14 wherein the input beam comprises a light beam.

16. The method of claim 15 wherein the first intensity component of the modulation signal corresponds to a first color intensity signal and wherein the second intensity component of the modulation signal corresponds to a second color intensity signal.

17. The method of claim 15 wherein the subparagraph (a) separating step is performed by passing the input beam through a polarizing beam splitter.

18. The method of claim 17 wherein the subparagraph (a) separating step is performed by passing the input beam through a polarizing cube.

19. The method of claim 17 wherein the subparagraph (b) rotating step is performed by passing the second beam segment through a half wave retarder.

20. The method of claims 14 or 15 wherein the first wavelength component includes a first band of wavelengths and wherein the second wavelength component includes a second band of wavelengths.

21. The method of claim 20 wherein the first and second bands of wavelengths are substantially non-overlapping.

22. The method of claims 14 or 15 wherein the first and second fixed E vector polarizations are substantially orthogonal.

23. The method of claim 14 wherein the E vector rotating steps of subparagraphs (e) and (f) are performed within first and second LCDs.

24. The method of claim 14 wherein the resolving step of subparagraph (h) is performed by directing the composite beam through a polarizing beam splitter.