Display system

• US 20010040670A1
• Filed: 07/30/2001
• Published: 11/15/2001
• Est. Priority Date: 08/04/1994
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Fielding, Raymond G.
• Granted Patent: US 6,631,993 B2
• Time in Patent Office: Days
• US Class Current: 353/31
• CPC Class Codes: G02B 26/0833 the reflecting element being a micromechanical device, e.g. a MEMS mirror, DMD G02B26/0825 takes precedence; micromechanical devices in general B81B
• CPC Class Codes: H04N 5/74 Projection arrangements for image reproduction, e.g. using eidophor
• CPC Class Codes: H04N 5/7458 the modulator being an array of deformable mirrors, e.g. digital micromirror device [DMD]
• CPC Class Codes: H04N 9/3114 by using a sequential colour filter producing one colour at a time

Abstract

A projecting display system includes a light source (101) which produces light which is spatially modulated by a number of spatial light modulators (105, 107). A splitting means (103) is provided in the light path between the light source (101) and the spatial light modulators (105 and 107) such that the overall luminous flux produceabale by the system is not determined by the maximum luminous flux which each spatial light modulators (105, 107) can accommodate.

Claims

1. A display system comprising:

a light source;

at least two deflectable mirror arrays effective to spatially modulate incident light with the same pattern;

means for splitting light of the same spectral composition from the light source between the spatial light modulators;

means for combining the spatially modulated light produced by the deflectable mirror arrays to create an image for projection onto a display; and

means for directing the combined light onto a display to form an image, the system being such that the combined light forming the image has a greater luminous flux than the light produced by each deflectable mirror array.

4. A display system according to any one of the preceding claims wherein each deflectable mirror array is effective to reflect spatially modulated light, and wherein said means for splitting light is arranged additionally to combine the spatially modulated light reflected by the spatial light modulators.

5. A display system according to any one of the preceding claims wherein said means for splitting light comprises at least one polarized splitter effective to split the light incident thereon into P-polarized light and S-polarized light components.

6. A display system according to any one of the preceding claims wherein said means for splitting light comprises:

at least one semi-reflective means which is effective to reflect part of the light incident thereon and to transmit the rest of the light incident thereon.

7. A display system according to any one of the preceding claims wherein said means for splitting light comprises a dichroic means.

8. A display system according to

claim 7

wherein the dichroic means is arranged to split light within the same primary colour band.

9. A display system according to

claim 8

in which there are provided at least two spatial light modulators in respect of two wavelength bands in the green light spectrum.

10. A display system according to any one of the preceding claims wherein each spatial light modulator is effective to reflect spatially modulated light, and in which the number of reflective means provided in the light path causes the spatially modulated combined light to undergo compensatory reflections to correct for any handedness imported by the spatial light modulators on the spatially modulated light.

11. A display system according to

claim 1

and any one of

claims 3

to

10

when dependent on

claim 1

, including means for sequentially directing light of different spectral compositions through the display system.

13. A projection system including a display system according to any one of

claims 1

to

12

and a projection screen.

14. A method of using a display system as claimed in any one of

claims 1

to

13

.

2. A display system comprising:

a multi wavelength light source;

a plurality of deflectable mirror arrays each effective to spatially modulate incident light with a different wavelength band component of the same pattern;

wavelength selective means for light within each different wavelength bands towards the corresponding deflectable mirror;

means for combining the spatially modulated light produced by the deflectable mirror array; and

means for directing the combined light onto a display;

wherein there are provided sufficient spatial light modulators to increase the balance of the division of the luminous flux produced by the light source between the spatial light modulators.

3. A display system according to either of the preceding claims wherein said means for displaying comprises:

means for projecting the combined light onto a projection screen.

12. A display system substantially as hereinbefore described with reference to FIGS. 1, 2 and 3 of the accompanying drawings.