Color display system using spatial light modulators

• US 5,231,388 A
• Filed: 12/17/1991
• Issued: 07/27/1993
• Est. Priority Date: 12/17/1991
• Status: Expired due to Term

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Stoltz, Richard A.
• Primary Examiner(s): Weldon, Ulysses
• Application Number:
  US07/809,362
• Time in Patent Office: 588 Days
• Field of Search: 340/701-703, 340/783, 340/752, 353/31, 358/62, 358/89
• US Class Current: 345/84
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means
• CPC Class Codes: G09G 3/2077 by a combination of two or more gradation control methods
• CPC Class Codes: G09G 3/346 based on modulation of the reflection angle, e.g. micromirrors micromirrors devices per se G02B26/0833
• CPC Class Codes: H04N 5/7458 the modulator being an array of deformable mirrors, e.g. digital micromirror device [DMD]
• CPC Class Codes: H04N 9/3126 for spatial light modulators in series

Abstract

A color display system for transforming pixel data, where each of three primary colors is represented by a value for its intensity, into an image. Three light sources, 11a-11c, one for each primary color, each illuminate a spatial light modulator (SLM) 12a -12c, such as a deformable mirror device. Each of these SLMs 12a-12c is operated so that it reflects an amount of light corresponding to the intensity of the pixel currently being displayed. The light thus regulated is linearized into a single beam of mixed-color light using mirrors 14a, 14b, and lens 15, and directed to an addressing SLM 13. Addressing SLM 13 is operated so that only an element corresponding to the pixel being displayed is "on". The addressing SLM 13 reflects the mixed-color light for that pixel to a photosensitive surface 18.

Claims

1. A color display system for displaying an image from an incoming data signal comprised of data representing the image in terms of pixels, where each pixel has color data representing an intensity of each of three primary colors, comprising:

a set of light sources, one for each primary color;

a set of color-regulating spatial light modulators (SLMs), wherein each of said color-regulating SLMs receives light from only one of said light sources, and wherein each of said color-regulating SLMs comprises an array of pixel elements, each pixel element comprising;

a reflective, active area;

addressing circuitry arrange such that each element is individually addressable, and when addressed with an on signal, the element reflects light in a specified direction;

a means for linearizing light, arranged in said specified direction so as to receive light from said color-regulating SLMs toward an addressing SLM; and

an addressing SLM, wherein said SLM comprises an array of pixel elements with addressing circuitry arranged so that each element is individually addressable, for receiving said linearized light beam and for reflecting said beam to a photosensitive surface.

2. The system of claim 1, wherein said linearizing means combines light from each of said color-regulating SLMs such that a single mixed light beam is produced.

3. The system of claim 1, wherein said linearizing means directs light along a path for each color and wherein a number of addressing SLMs each receive light from one of said paths.

4. The system of claim 1, wherein said color-regulating SLMs are deformable mirror devices.

5. The system of claim 1, and further comprising control means for loading said color-regulating SLMs in accordance with said incoming data.

6. The system of claim 1, further comprising timing means coupled to said addressing circuitry of said addressing SLM so that as each pixel of said addressing SLM is addressed, its color is adjusted by said color-regulating SLMs.

7. The system of claim 1, wherein said photosensitive surface is a display screen.

8. The system of claim 1, and further comprising at least one additional set of light sources and color-regulating SLMs.

9. The system of claim 1, wherein said photosensitive surface is photosensitive film.

10. The system of claim 1, wherein each of said pixel elements of said addressing SLM is divided into individually addressable pixel sections, each for receiving a single color of light from said color-regulating SLMs.

11. A method for forming a color image from an incoming signal comprised of data representing the image in terms of pixels, wherein each pixel has color data representing an intensity of each of several different colors, comprising the steps of:

addressing a pixel element of an addressing spatial light modulator (SLM), wherein said element has addressing circuitry which actuates said cell, such that only said addressed pixel element can reflect light in predetermined path;

generating a number of beams of light, each of a different color;

receiving each of said beams of light at an associated color-regulating SLM;

adjusting the number of pixel elements of said color-regulating SLM that will reflect said light along said predetermined path;

linearizing light reflected from each of said color-regulating SLMs on a path toward said addressing SLM;

receiving said linearized light at said addressing SLM;

receiving light reflected from said addressing SLM on a photosensitive surface; and

repeating the above steps for a next pixel element until a complete image frame is generated on said photosensitive surface.

12. The method of claim 11, and further comprising the step of linearizing light reflected from each of said color-regulating SLMs along a predetermined path to form a single mixed color light beam.

13. The method of claim 11, and further comprising the step of receiving light reflected from said addressing SLM on a photosensitive surface is accomplished with a display screen.

14. The method of claim 11, and further comprising the step of timing said steps such that they occur in real time with said incoming signal.

15. The method of claim 11, wherein said adjusting step is achieved by loading more than one part of said color-regulating SLM simultaneously.

16. The method of claim 11, wherein more than one pixel element of said addressing SLM is addressed at one time, and said steps are duplicated for each of said simultaneously addressed pixels.

17. The method of claim 11, and further comprising the step of receiving light reflected from said addressing SLM on a photosensitive film for recording a still picture.

18. The method of claim 11, and further comprising the step of receiving light reflected from said addressing SLM at a photosensitive sensor that generates an electronic signal.

19. A color display system for displaying an image from an incoming data signal comprised of data representing the image in terms of pixels, where each pixel has color data representing an intensity of each of three primary colors, comprising:

a processor for transforming said incoming data;

a frame buffer for receiving and storing said data on a frame by frame basis;

an optics unit having a set of light sources, one for each primary color, a set of color-regulating spatial light modulators (SLMs), wherein each of said color-regulating SLMs receives light from one of said light sources, and wherein each of said color-regulating SLMs comprises an array of pixel elements that may all be switched on or off simultaneously, a means for linearizing light from said color-regulating SLMs toward an addressing SLM, and an addressing SLM for receiving said linearized light beam and for reflecting said beam, wherein said addressing SLM comprises an array of individually addressable pixel elements; and

a photosensitive surface for receiving light reflected from said addressing SLM.

20. The system of claim 19, wherein said processor has timing means for controlling said color-regulating SLMs and said addressing SLM such that said image is received at said photosensitive surface in real time relative to said incoming signal.

21. The system of claim 19, wherein said color-regulating SLMs are deformable mirror devices.