Methods and apparatus for optical display using multiple spatial light modulators for increased resolution

Patent metadata

Field	Value
Publication number	US-9344696-B2
Application number	US-201514808893-A
Country	US
Kind code	B2
Filing date	Jul 24, 2015
Priority date	Jul 29, 2014
Publication date	May 17, 2016
Grant date	May 17, 2016

Abstract

A system for displaying a high resolution video image utilizing multiple spatial light modulators includes at least one illumination source configured to provide illumination to multiple spatial light modulators; a video data image processor coupled to receive video image data at a first visual resolution of X by Y pixels; and multiple spatial light modulators each having an image resolution lower than the first visual resolution, each configured to project an image sub-frame onto a focal plane using an image projection system; wherein the image projection system is configured to project a first sub-frame image of a first color portion while simultaneously projecting at least a second sub-frame image of a second color portion onto the focal plane, and the first and second sub-frame images are offset from one another, so that when viewed together a viewed image has at least the first visual resolution. Methods are disclosed.

First claim

What is claimed is:

1. A method for displaying images, comprising:
receiving video image data signal in a display system capable of displaying images, the video image data signal having a first resolution;
forming from the video image data signal a first sub-frame image and a second sub-frame image, each of the first and second sub-frame images having a second resolution that is lower than the first resolution;
for a first offset frame time that is less than a frame display time, simultaneously projecting a first color portion for the first sub-frame image and a second color portion for the second sub-frame image onto a focal plane; and
for a second offset frame time that is less than the frame display time, simultaneously projecting a second color portion for the first sub-frame image and a first color portion for the second sub-frame onto the focal plane;
wherein the first sub-frame and the second sub-frame are spatially offset by an offset distance that is less than a pixel pitch in the first and second sub-frames, and wherein the first color portion and the second color portion viewed together comprise color information needed to view the video image in the first resolution and in color.

2. The method of claim 1 , wherein projecting the first sub-frame image and projecting the second sub-frame image further comprises projecting the first sub-frame image using a first spatial light modulator, and projecting the second sub-frame image using a second spatial light modulator.

3. The method of claim 1 , wherein projecting the first sub-frame image and projecting the second sub-frame image further comprises projecting the first sub-frame image and the second sub-frame image using an optical actuator to shift the sub-frame images by a predetermined distance.

4. The method of claim 1 wherein the first sub-frame and the second sub-frame are spatially offset by a diagonal offset.

5. The method of claim 1 wherein the first sub-frame and the second sub-frame are spatially offset by an offset in one of horizontal and vertical directions.

6. The method of claim 1 and further comprising:
wherein the first color portion comprises at least one of red, green and blue color information from the video image data signal.

7. The method of claim 6 wherein the first color portion comprises the green color information from the video image data signal.

8. The method of claim 7 wherein the second color portion comprise the blue and red color information from the video image data signal.

9. The method of claim 6 , wherein the second color portion comprises a color different than the first color portion that comprises at least two of the red, green and blue color information from the video image data signal.

10. The method of claim 1 , wherein a sum of the first and second offset frame times is less than or equal to the frame display time.

11. The method of claim 10 , wherein the first and second offset frame times are equal.

12. The method of claim 1 , wherein:
the first sub-frame image and the second sub-frame image each comprise a plurality of pixels arranged in rows and columns; and
the offset is an offset approximately half of a width and half of a height of one of the pixels.

13. The method of claim 2 wherein providing the first and second spatial light modulators further comprises providing a digital micro-mirror device.

14. The method of claim 2 wherein providing the first and second spatial light modulators further comprises providing a spatial light modulator that is one selected from a group consisting essentially of a digital micro-mirror device and a liquid crystal on silicon device.

15. The method of claim 14 , wherein forming from the video image data signal a first sub-frame image and a second sub-frame image further comprises:
receiving the video data image data signal having a visual resolution of X by Y pixels including color information comprising at least red, green and blue colors for each of the pixels;
dividing the image into a first sub-frame and a second sub-frame, each sub-frame having a number of pixels that is less than X by Y pixels;
using a first spatial light modulator, displaying the first sub-frame in a first color for a first offset frame display period;
using a second spatial light modulator, displaying the second sub-frame in a second color different from the first color simultaneously with the first sub-frame in the first color;
using the first spatial light modulator, displaying the first sub-frame in the second color for a second offset frame display period; and
using the second spatial light modulator, displaying the second sub-frame in the first color simultaneously with displaying the first sub-frame in the second offset frame display period;
wherein the first and second sub-frames are simultaneously displayed and have a spatial offset in a diagonal direction, the spatial offset being less than a spacing of the pixels, each of the first and second sub-frames having a visual resolution that less than the resolution of X by Y pixels, and wherein the resolution of a displayed image composed of the first and second sub-frames provides a visual resolution of at least X by Y pixels.

16. The method of claim 14 , and further comprising:
after forming the first and second sub-frame images having a diagonal offset of less than one pixel pitch between the first and second sub-frame images, applying an inverse filter to offset for pixel overlap effects to the first and second sub-frame images and to compensate for an amount of fill factor.

17. A method for displaying images having increased visual resolution, comprising:
providing an image projection system configured to simultaneously project a sub-frame image for each of at least two spatial light modulators onto a focal plane, each of the spatial light modulators having a first resolution of at least X by Y pixels;
receiving visual image data, the visual image data including at least red, green and blue color information at a first image resolution greater than the first resolution;
using the visual image data, forming an intermediate image having a resolution of approximately twice the first resolution;
forming an inverse filter configured to compensate for pixel overlap in the intermediate image;
convolving the intermediate image with the inverse filter to form a compensated image;
forming a sub-frame image for display at each of the at least two spatial light modulators by sampling the compensated image to form first and second sub-frame images having a first color portion of the visual image data for each of the at least two spatial light modulators, the spatial light modulators each being configured to display different color portions of the visual image data;
simultaneously projecting for a first offset frame time the first and second sub-frame images for the first color portion on a focal plane, the first sub-frame image and the second sub-frame being spatially offset in a direction by a portion of a pixel pitch; and
simultaneously projecting for a second offset frame time on the focal plane a second color portion for the first sub-frame image and the second sub-frame image for each of the spatial light modulators, the first and second sub-frame images viewed together forming an image having all of the color information of the visual image data and having an image resolution greater than or equal to the first resolution.

18. The method of claim 17 , wherein providing the at least two spatial light modulators further comprises providing a first spatial light mo

Assignees

• Texas Instruments Inc

Inventors

• Kempf Jeffrey Matthew
• Pettitt Gregory Scott
• Davis Michael Terry

Classifications

• G06T3/40

  Scaling of whole images or parts thereof, e.g. expanding or contracting · CPC title

• H04N9/3188 Primary

  Scale or resolution adjustment (scaling in general G06T3/40; resolution modifying circuits for displays in general G09G5/391) · CPC title

• G09G5/18

  Timing circuits for raster scan displays (specially adapted for television H04N {; synchronisation between the display unit and other display units, videodisc player G09G5/12}) · CPC title

• G09G5/02

  characterised by the way in which colour is displayed {(details of colour display specific for CRTs G09G1/28; specific for flat matrix panels other than liquid crystal displays G09G3/2003; specific for liquid crystal displays G09G3/3607)} · CPC title

• H04N9/3105

  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 title