Display architectures using an electronically controlled optical retarder stack

• US 6,273,571 B1
• Filed: 10/01/1999
• Issued: 08/14/2001
• Est. Priority Date: 05/23/1995
• Status: Expired due to Term

• Current Assignee: RealD Incorporated
• Original Assignee: ColorLink, Incorporated (RealD Incorporated)
• Inventors: Sharp, Gary D., Johnson, Kristina M.
• Primary Examiner(s): DOWLING, WILLIAM C
• Application Number:
  US09/410,098
• Time in Patent Office: 683 Days
• Field of Search: 353/31, 353/34, 353/37, 353/122, 353/84, 353/20, 349/5, 349/18, 348/742
• US Class Current: 353/122
• CPC Class Codes: G02B 27/288 Filters employing polarising elements, e.g. Lyot or Solc filters G02B5/3016 takes precedence
• CPC Class Codes: G02B 5/3083 Birefringent or phase retarding elements G02B5/3008, G02B5/3016 take precedence; systems for polarisation control G02B27/286; manufacturing phase modulating patterns by lithographic processes G03F7/001
• CPC Class Codes: G02F 1/0136 for the control of polarisation, e.g. state of polarisation [SOP] control, polarisation scrambling, TE-TM mode conversion or separation G02F1/0353 takes precedence
• CPC Class Codes: G02F 1/0322 Arrangements comprising two or more independently controlled crystals
• CPC Class Codes: G02F 1/09 based on magneto-optical elements, e.g. exhibiting Faraday effect
• CPC Class Codes: G02F 1/133533 Colour selective polarisers G02F1/1347 takes precedence
• CPC Class Codes: G02F 1/133536 Reflective polarizers G02F1/13362 takes precedence
• CPC Class Codes: G02F 1/133543 Cholesteric polarisers
• CPC Class Codes: G02F 1/1336 Illuminating devices
• CPC Class Codes: G02F 1/13362 providing polarized light, e.g. by converting a polarisation component into another one
• CPC Class Codes: G02F 1/13363 Birefringent elements, e.g. for optical compensation
• CPC Class Codes: G02F 1/133638 Waveplates, i.e. plates with a retardation value of lambda/n
• CPC Class Codes: G02F 1/13473 for wavelength filtering or for colour display without the use of colour mosaic filters
• CPC Class Codes: G02F 1/23 for the control of the colour G02F1/03 - G02F1/21 take precedence
• CPC Class Codes: G02F 2413/04 Number of plates greater than or equal to 4
• CPC Class Codes: G02F 2413/08 with a particular optical axis orientation
• CPC Class Codes: H04N 5/66 Transforming electric information into light information scanning details H04N3/00
• CPC Class Codes: H04N 5/7441 the modulator being an array of liquid crystal cells
• CPC Class Codes: H04N 9/3167 for polarizing the light beam polarizing optical systems per se G02B27/28

Abstract

A system architecture for a display system with electronically controlled optical retarder stacks. The system uses only one spatial light modulator and a color filter to determine what the color of the image created by the modulator will be when projected onto a display surface. In one embodiment, the color filter passes one of red, green or blue light at any give time. The color filter can be placed between the light source and the modulator optics, between the modulator optics and the modulator, between the modulator and the projection optics, or made part of the projection optics itself. The retarder stack for transforming at least partially polarized input light can include a first retarder and a second retarder. The first retarder has a first retardance and a first orientation and the second retarder has a second retardance and a second orientation, both orientations with respect to the partially polarized light. The first retardance, first orientation, second retardance, and second orientation can be arranged to yield the desired polarization transformed light which includes a first spectrum and a second spectrum. The polarization of the first spectrum and the polarization of the second spectrum can be made orthogonal to each other. The polarizations can be linear or elliptical. If the polarization transformed light is linear, the directions of polarizations are different and in one case can be made perpendicular. If the polarization of the polarization transformed light is elliptical, then the polarizations are different and in on case can be made orthogonal in the general sense of orthogonality of polarization states.

Claims

1. A display system, comprising:

input optics that receive and direct at least partially polarized input light;

an electronically controllable spectral sequencer that sequentially outputs spectra of light, the spectral sequencer including at least;

a first retarder stack;

a second retarder stack; and

an electronically controllable single pixel modulator optically coupled to the first and second retarder stacks;

only one spatial light modulator optically coupled to the electronically controllable spectral sequencer, wherein the only one spacial light modulator and the electronically controllable spectral sequencer receive the at least partially polarized input light directed by the input optics and output a plurality of modulated patterns of light with sequentially varying spectra; and

projection optics that receive and project the plurality of modulated patterns of light onto a display surface.

2. The display system of claim 1, wherein the spectral sequencer controls the light projected onto the display surface such that the plurality of modulated patterns includes a separate modulated pattern for each of the spectra of the input light, and

the control of the single pixel modulator is coordinated with sequential modulation of the spatial light modulator to create the separate modulated patterns.

3. The display system of claim 1, wherein the light comprises visible light.

4. The display system of claim 3, wherein the spectra are the additive primary colors.

5. The display system of claim 1, wherein the light comprises infrared light.

6. The display system of claim 1, wherein the light comprises ultraviolet light.

7. The display system of claim 1, wherein the spatial light modulator is a transmissive spatial light modulator.

8. The display system of claim 1, wherein the spatial light modulator is a reflective spatial light modulator.

9. The display system of claim 1, wherein the spatial light modulator is located optically between the input optics and the spectral sequencer.

10. The display system of claim 1, wherein the spatial light modulator is located optically between the spectral sequencer and the projection optics.

11. The display system of claim 1, wherein the spatial light modulator is located optically between a first electronically controllable single pixel modulator and a second electronically controllable single pixel modulator.

12. The display system of claim 2, wherein,

the first retarder stack receives the input light from the input optics and provides a first transformation of the input light into transformed light having a spectrum and polarization that is different than the spectrum and polarization of the input light, and;

the second retarder stack receives at least a portion of the transformed light and provides a second transformation that transforms the transformed light into output light with a spectrum and polarization which is substantially the same as the spectrum and polarization of the input light.

13. The display system of claim 12, wherein the plurality of spectra are the additive primary colors.

14. A display system comprising:

input optics that receive and direct at least partially polarized input light;

an electronically controllable spectral sequencer that sequentially outputs spectra of light, the spectral sequencer including at least;

a retarder stack; and

an electronically controllable single pixel modulator optically coupled to the retarder stack;

only one spatial light modulator optically coupled to the electronically controllable spectral sequencer, wherein the only one spacial light modulator and the electronically controllable spectral sequencer receive the at least partially polarized input light directed by the input optics and output a plurality of modulated patterns of light with sequentially varying spectra; and

projection optics that receive and project the plurality of modulated patterns of light onto a display surface.

15. The display system of claim 14, wherein the spectral sequencer controls the light projected onto the display surface such that the plurality of modulated patterns includes a separate modulated pattern for each of the spectra of the input light, and

the control of the single pixel modulator is coordinated with sequential modulation of the spatial light modulator to create the separate modulated patterns.

16. The display system of claim 14, wherein the spectra are the additive primary colors.

17. A display system having only one spatial light modulator, the system comprising:

a radiation source;

input optics that direct at least partially polarized input electromagnetic radiation received from the radiation source to the spatial light modulator;

projection optics that receive a plurality of modulated patterns of electromagnetic radiation created by the spatial light modulator and project the plurality of modulated patterns onto a display surface;

an electronically controllable spectral sequencer that receives the input electromagnetic radiation and that sequentially outputs spectra of the received input electromagnetic radiation, the spectral sequencer having a plurality of sequencing units, each of the plurality of sequencing units comprising;

a first retarder stack that receives the input electromagnetic radiation from the input optics and provides a first transformation of the input electromagnetic radiation into transformed electromagnetic radiation;

a second retarder stack that receives at least a portion of the transformed electromagnetic radiation and provides a second transformation that transforms the transformed electromagnetic radiation into output electromagnetic radiation, wherein the first and second transformations polarize the output electromagnetic radiation into at least a first polarization state having a first spectrum and a second polarization state having a second spectrum; and

an electronically controllable single pixel modulator optically coupled to the first and second retarder stacks,

wherein the spectral sequencer controls the electromagnetic radiation projected onto the display surface such that the plurality of modulated patterns includes a separate modulated pattern for each of the spectra of the input electromagnetic radiation, and

the control of each of the single pixel modulators is coordinated with sequential modulation of the spatial light modulator to create the separate modulated patterns.

18. The display system of claim 17, wherein the single pixel modulators modify the polarization of the transformed electromagnetic radiation in a known fashion, and

the output electromagnetic radiation has a spectrum and polarization which is approximately the same as a spectrum and polarization of the input electromagnetic radiation.

19. A method of displaying an image, comprising:

directing at least partially polarized input light to only one spatial light modulator;

creating a plurality of modulated patterns of light by sequentially modulating the spatial light modulator and projecting the plurality of modulated patterns onto a display surface;

sequentially outputting spectra of light with an electronically controllable spectral sequencer optically coupled to the spatial light modulator, the spectral sequencer including at least;

a first retarder stack; and

an electronically controllable single pixel modulator optically coupled to the first retarder stack.

20. The method of claim 19, wherein the spectral sequencer controls the light projected onto the display surface such that the plurality of modulated patterns includes a separate modulated pattern for each of the spectra of light, and

the control of the single pixel modulator is coordinated with sequential modulation of the spatial light modulator to create the separate modulated patterns.