Display apparatus including RGB color combiner and 1D light valve relay including schlieren filter

• US 6,692,129 B2
• Filed: 09/05/2002
• Issued: 02/17/2004
• Est. Priority Date: 11/30/2001
• Status: Active Grant

• Current Assignee: Silicon Light Machines Corporation (SCREEN Holdings Co., Ltd.)
• Original Assignee: Silicon Light Machines Corporation (SCREEN Holdings Co., Ltd.)
• Inventors: Buchroeder, Richard A., Manhart, Paul, Gross, Kenneth P.
• Primary Examiner(s): Adams, Russell
• Assistant Examiner(s): Cruz, Magda
• Application Number:
  US10/237,239
• Publication Number:
  US 20030103194A1
• Time in Patent Office: 530 Days
• Field of Search: 353/31, 353/20, 353/84, 353/122, 353/98, 348/762, 348/767, 348/759, 348/795, 359/28, 359/259, 359/316, 359/588, 359/590, 349/30, 382/211, 385/1, 356/518, 356/129, 356/362
• US Class Current: 353/31
• CPC Class Codes: G03B 21/10 Projectors with built-in or built-on screen
• 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 9/3132 using one-dimensional electronic spatial light modulators
• CPC Class Codes: H04N 9/3164 using multiple light sources

Abstract

The optical system includes a plurality of light modulators, one or more combining filters, and an optical relay system including a filter. Each light modulator modulates a corresponding incident light beam. The one or more combining filters superimpose the modulated light beams from each of the plurality of light modulators. The optical relay system filters the superimposed light and relays the filtered light to an image plane.

Claims

1. An optical system comprising:

(a.) a plurality of light modulators, wherein each light modulator modulates a corresponding incident light beam;

(b.) one or more combining filters for superimposing the modulated light beams from each of the plurality of light modulators; and

(c.) an optical relay system including a filter, a primary mirror and a secondary mirror, wherein the optical relay system filters the superimposed light and relays the filtered light to an image plane.

2. The optical system according to claim 1 wherein each light modulator includes a grating light valve type device.

3. The optical system according to claim 1 wherein the optical relay system includes a modified Offner relay type device including the primary mirror and the secondary mirror.

4. The optical system according to claim 3 wherein the primary mirror receives the superimposed light from the one or more combining filters off-axis.

5. The optical system according to claim 3 wherein the filter within the modified Offner relay type device is located at a transform plane of the modified Offner relay type device.

6. The optical system according to claim 5 wherein the secondary mirror includes the filter.

7. The optical system according to claim 1 wherein the filter within the optical relay system includes a Schlieren type filter.

8. The optical system according to claim 1 wherein the combining filters include dichroic filters.

9. The optical system according to claim 1 wherein each light modulator modulates the light by reflecting a portion of the incident light beam as zero order light and by diffracting another portion of the incident light beam as first order light.

10. The optical system according to claim 9 wherein the zero order light is relayed to the image plane.

11. The optical system according to claim 9 wherein the first order light is relayed to the image plane.

12. The optical system according to claim 1 further comprising a color correction lens coupled between one or more of the plurality of light modulators and the combining filters.

13. A method of combining, relaying and filtering a plurality of light beams comprising:

(a.) modulating each of the plurality of light beams;

(b.) combining each of the modulated light beams;

(c.) relaying the combined light beams to an image plane using a primary mirror and a secondary mirror; and

(d.) filtering the combined light beam while the combined light beam is relayed to the image plane.

14. The method according to claim 13 wherein each of the plurality of light beams is modulated by reflecting a portion of the light beam as zero order light and by diffracting another portion of the light beam as first order light.

15. The method according to claim 14 wherein the combined light beams are filtered by passing the zero order light and reflecting the first order light such that the first order light is relayed to the image plane.

16. The method according to claim 14 wherein the combined light beams are filtered by passing the first order light and reflecting the zero order light such that the zero order light is relayed to the image plane.

17. An optical system comprising:

(a.) means for modulating each of the plurality of light beams;

(b.) means for combining each of the modulated light beams;

(c.) means for relaying the combined light beams to an image plane, wherein the means for relaying comprises a primary mirror and a secondary mirror; and

(d.) means for filtering the combined light beam while the combined light beam is relayed to the image plane.

18. The optical system according to claim 17 wherein the means for modulating comprises a plurality of grating light valve type devices, each grating light valve type device corresponding to one of the plurality of light beams.

19. The optical system according to claim 18 wherein the means for relaying comprises a modified Offner relay type device including the primary mirror and the secondary mirror.

20. The optical system according to claim 19 wherein the means for filtering comprises the secondary mirror such that the secondary mirror is configured as a Schlieren type filter.