Six color display apparatus having increased color gamut

• US 6,769,772 B2
• Filed: 10/11/2002
• Issued: 08/03/2004
• Est. Priority Date: 10/11/2002
• Status: Expired due to Term

• Current Assignee: IMAX Theatres International Limited (IMAX Corporation)
• Original Assignee: Eastman Kodak Company
• Inventors: Zolla, Robert J., Roddy, James E., Blish, Nelson A., Horvath, Louis S.
• Primary Examiner(s): Sever, Andrew T.
• Application Number:
  US10/269,314
• Publication Number:
  US 20040070736A1
• Time in Patent Office: 662 Days
• Field of Search: 353/29-34, 353/94, 353/48, 353/7, 353/8, 353/81, 353/84, 353/85-87, 353/122, 349/5, 349/8, 349/9, 349/10, 349/15
• US Class Current: 353/31
• CPC Class Codes: G03B 21/00 Projectors or projection-type viewers; Accessories therefor devices for changing pictures G03B23/00
• CPC Class Codes: H04N 9/3158 for controlling the spectrum
• CPC Class Codes: H04N 9/3188 Scale or resolution adjustment scaling in general G06T3/40; resolution modifying circuits for displays in general G09G5/391

Abstract

A display system (10) for digital color images using six color light sources (12) or two or more multicolor LED arrays (212, 213) or OLEDs (220, 222) to provide an expanded color gamut. Apparatus (10) uses two or more spatial light modulators (20, 21), which may be cycled between two or more color light sources (12) or LED arrays (212, 213) to provide a six-color display output. Pairing of modulated colors using relative luminance helps to minimize flicker effects.

Claims

1. An apparatus for displaying a color image from digital data, the apparatus comprising:

(a) first modulation system for providing a first modulated beam, said first modulation system comprising;

(a1) a first spatial light modulator for modulating a first incident light beam in order to form said first modulated beam according to said digital data;

(a2) a first light source for providing a first color beam as said first incident light beam;

(a3) a second light source for providing a second color beam as said first incident light beam;

(b) second modulation system for providing a second modulated beam, said second modulation system comprising;

(b1) a second spatial light modulator for modulating a second incident light beam in order to form said second modulated beam according to said digital data;

(b2) a third light source for providing a third color beam as said second incident light beam;

(b3) a fourth light source for providing a fourth color beam as said second incident light beam;

(c) third modulation system for providing a third modulated beam, said third modulation system comprising;

(c1) a third spatial light modulator for modulating a third incident light beam in order to form said third modulated beam according to said digital data;

(c2) a fifth light source for providing a fifth color beam as said third incident light beam;

(c3) a sixth light source for providing a sixth color beam as said third incident light beam; and

(d) an optical combiner for directing said first, second, and third modulated beams toward a lens for projection onto a display surface.

2. An apparatus for displaying a color image according to claim 1 wherein said first modulation system further comprises a polarization beamsplitter for directing polarized light from said first light source to form said first modulated beam.

3. An apparatus for displaying a color image according to claim 1 wherein said polarizer is a wire-grid polarizer.

4. An apparatus for displaying a color image according to claim 1 wherein said first light source is taken from the group consisting of LEDs and lasers.

5. An apparatus for displaying a color image according to claim 1 further comprising a uniformizer for providing said first color beam having a uniform field.

6. An apparatus for displaying a color image according to claim 5 wherein said uniformizer is from the group consisting of lenslet array, integrator bar, integrating tunnel.

7. An apparatus for displaying a color image according to claim 5 wherein said uniformizer adapts the aspect ratio of said first incident light beam to the aspect ratio of said first spatial light modulator.

8. An apparatus for displaying a color image from digital data according to claim 1 wherein the resolutions of said first, second, and third spatial light modulators are not all equal.

9. An apparatus for displaying a color image from digital data, the apparatus comprising:

(a) a first spatial light modulator for modulating a first incident light beam from a first light source to form a first color modulated beam;

(b) a second spatial light modulator for modulating a second incident light beam from a second light source to form a second color modulated beam;

(c) a third spatial modulator for modulating a third incident light beam from a third light source to form a third color modulated beam;

(d) a fourth spatial light modulator for modulating a fourth incident light beam from a fourth light source to form a fourth color modulated beam;

(e) a fifth spatial light modulator for modulating a fifth incident light beam from fifth light source to form a fifth color modulated beam;

(f) a sixth spatial light modulator for modulating a sixth incident light beam from a sixth light source to form a sixth color modulated beam;

(g) means for combining said first, second, third, fourth, fifth, and sixth color modulated beams to form a combined color beam;

(h) means for projection of said combined color beam onto a display surface; and

wherein the resolutions of said first, second, third, fourth, fifth, and sixth spatial light modulators are not all equal.

10. An apparatus for displaying a color image from digital data according to claim 9 further comprising means for uniformizing said first color modulated beam.

11. An apparatus for displaying a color image from digital data according to claim 9 wherein said first light source is taken from the set consisting of laser, LED.

12. A method for displaying a color image from digital data, the method comprising:

(a) forming a first modulated beam by;

(a1) providing a first color beam from a first light source;

(a2) providing a second color beam from a second light source;

(a3) in a repeated sequence, alternately directing said first and said second color beam to a first spatial light modulator as a first incident light beam, said first spatial light modulator modulating said first incident light beam as an array of pixels to form said first modulated beam;

(b) forming a second modulated beam by;

(b1) providing a third color beam from a third light source;

(b2) providing a fourth color beam from a fourth light source;

(b3) in a repeated sequence, alternately directing said third and said fourth color beam to a second spatial light modulator as a second incident light beam, said second spatial light modulator modulating said second incident light beam as an array of pixels to form said second modulated beam;

(c) forming a third modulated beam by;

(c1) providing a fifth color beam from a fifth light source;

(c2) providing a sixth color beam from a sixth light source;

(c3) in a repeated sequence, alternately directing said fifth and said sixth color beam to a third spatial light modulator as a third incident light beam, said third spatial light modulator modulating said third incident light beam as an array of pixels to form said third modulated beam; and

(d) combining said first, second, and third modulated beams to form an output beam and projecting said output beam onto a surface in order to form the color image.

13. A method for displaying a color image according to claim 12 wherein the step of combining uses a dichroic prism.

14. A method for displaying a color image according to claim 12 wherein said first, second, and third modulated beams do not have the same resolution.

15. A method for displaying a color image from digital data, the method comprising:

(a) forming a first modulated beam by modulating a first color beam at a first spatial light modulator;

(b) forming a second modulated beam by modulating a second color beam at a second spatial light modulator;

(c) forming a third modulated beam by modulating a third color beam at a third spatial light modulator;

(d) forming a fourth modulated beam by modulating a fourth color beam at a fourth spatial light modulator;

(e) forming a fifth modulated beam by modulating a fifth color beam at a fifth spatial light modulator;

(f) forming a sixth modulated beam by modulating a sixth color beam at a sixth spatial light modulator;

(g) combining said first, second, third, fourth, fifth, and sixth modulated beams to form a multicolor beam and projecting said multicolor beam onto a display surface; and

wherein said first spatial light modulator differs in resolution from at least one of said second, third, fourth, fifth, and sixth spatial light modulators.

16. A method for minimizing flicker in a digital display system that modulates, in a display sequence, a first, a second, a third, a fourth, a fifth, and a sixth color respectively from a first, a second, a third, a fourth, a fifth, and a sixth color source, the method comprising the steps of:

(a) arranging said first, second, third, fourth, fifth, and sixth colors in a luminance sequence in order of highest, second highest, third highest, fourth highest, fifth highest, and sixth highest relative luminance value;

(b) using said luminance sequence, grouping said first, second, third, fourth, fifth and sixth colors into first, second, and third pairs, such that each said pair contains one of said first, second, third, fourth, fifth, and sixth colors having highest, second highest, or third highest relative luminance value and one of said first, second, third, fourth, fifth, and sixth colors having fourth highest, fifth highest, or sixth highest relative luminance value; and

(c) sequentially modulating said first, second, third, fourth, fifth, and sixth colors in sequence of said first, second, and third pairs, thereby smoothing the luminance transition between colors.

17. A method for minimizing flicker in a digital display system accordin to claim 16 further comprising the step of adjusting luminance for at least one of said first, second, third, fourth, fifth, and sixth colors by adjusting power to the corresponding at least one of said first, second, third, fourth, fifth, and sixth color source.