OR-function illumination in phased bitplanes in a high dynamic range projector

Patent metadata

Field	Value
Publication number	US-10070105-B2
Application number	US-201615054363-A
Country	US
Kind code	B2
Filing date	Feb 26, 2016
Priority date	Feb 26, 2016
Publication date	Sep 4, 2018
Grant date	Sep 4, 2018

Abstract

OR-function illumination in phased bitplanes in a high dynamic range projector is provided, which can be used to reduce flicker artifacts. The projector comprises: a light source; a premod display; a prime display, the premod display configured to modulate light from the light source to illuminate the prime display; and, a computing device. The computing device drives the prime display according to a phased sequence to transition the prime display from a leading bitplane to a following bitplane. The computing device is further configured to, at least in a time period corresponding to the prime display being driven according to the phased sequence, drive adjacent pixel groups of the premod display according to an OR-function of premod versions of respective portions of each of at least the leading bitplane and the following bitplane.

First claim

What is claimed is:

1. A projector comprising:
a light source; a premod display; a prime display, the premod display configured to modulate light from the light source to illuminate the prime display; and, a computing device configured to:
drive the prime display according to a phased sequence to transition the prime display from a leading bitplane to a following bitplane; and,
at least in a time period corresponding to the prime display being driven according to the phased sequence, drive adjacent pixel groups of the premod display according to an OR-function of premod versions of respective portions of each of at least the leading bitplane and the following bitplane.

2. The projector of claim 1 , wherein the OR-function of the premod versions of the respective portions of each of at least the leading bitplane, and the following bitplane comprises the OR-function of premod versions of each of corresponding bitplanes used to drive the prime display.

3. The projector of claim 1 , wherein the premod versions of each of corresponding bitplanes used to drive the prime display comprise blurred versions of each of corresponding bitplanes used to drive the prime display.

4. The projector of claim 1 , further comprising optics configured to one or more of convey images in the light conveyed from the premod display to the prime display and blur images in the light conveyed from the premod display to the prime display.

5. The projector of claim 1 , wherein the computing device is further configured to drive the premod display according to a global premod bitplane during respective time periods of the prime display being driven according to the leading bitplane and the following bitplane.

6. The projector of claim 1 , wherein each of the adjacent pixel groups of the premod display are driven according to a phased premod bitplane and are driven for a longer time period than each of corresponding pixel groups of the prime display.

7. The projector of claim 6 , wherein each of the adjacent pixel groups of the premod display, are driven according to a phased premod bitplane and for a time period which: starts at a beginning of an earliest driving period of a corresponding adjacent pixel group of the prime display; and ends at a respective ending of a latest following driving period of a corresponding adjacent following prime pixel group of the prime display.

8. The projector of claim 6 , wherein a first pixel group of the adjacent pixel groups of the premod display is driven for a respective time period which: begins during the prime display being driven according to the leading bitplane; and ends at a respective ending of a second driving period of a corresponding second prime pixel group of the prime display.

9. The projector of claim 6 , wherein a last pixel group of the adjacent pixel groups of the premod display is driven for a respective time period which: starts at a respective beginning of a second-last driving period of a corresponding previous pixel group of the prime display; and ends during the prime display being driven according to the following bitplane.

10. The projector of claim 1 , wherein the phased sequence comprises a phased bitplane and the adjacent pixel groups of the premod display are driven according to the OR-function of the premod versions of respective portions of the leading bitplane, the phased bitplane and the following bitplane, at least in the time period corresponding to the prime display being driven according to the phased bitplane.

11. The projector of claim 10 , wherein the computing device is further configured to: at least in the time period corresponding to the prime display being driven according to the phased bitplane, drive the adjacent pixel groups of the premod display in a respective sequence across the premod display according to a phased premod bitplane, wherein each portion of the phased premod bitplane comprises the OR-function of premod versions of corresponding portions of each of the leading bitplane, the phased bitplane and the following bitplane.

12. The projector of claim 1 , wherein the OR-function of the premod versions used to drive the premod display includes dither patterns.

13. The projector of claim 1 , wherein the adjacent pixel groups comprise adjacent reset groups.

14. The projector of claim 1 , wherein each of the premod display and the prime display comprises one or more of a DMD (digital micromirror device) and an LCOS (liquid crystal on silicon) display.

15. The projector of claim 1 , further comprising cascade optics configured to convey modulated light rom the premod display to the prime display.

16. A method comprising:
at a projector comprising: a light source; a premod display; a prime display, the premod display configured to modulate light from the light source to illuminate the prime display, and a computing device, driving, using the computing device, the prime display according to a phased sequence to transition the prime display from a leading bitplane to a following bitplane; and,
at least in a time period corresponding to the prime display being driven according to the phased sequence, driving, using computing device, adjacent pixel groups of the premod display according to an OR-function of premod versions of respective portions of each of at least the leading bitplane and the following bitplane.

17. The method of claim 16 , wherein the OR-function of the premod versions of the respective portions of each of at least the leading bitplane, and the following bitplane comprises the OR-function of premod versions of each of corresponding bitplanes used to drive the prime display.

18. The method of claim 16 , wherein each of the adjacent pixel groups of the premod display are driven according to a phased premod bitplane and are driven for a longer time period than each of corresponding pixel groups of the prime display.

19. The method of claim 16 , wherein the phased sequence comprises a phased bitplane and the adjacent pixel groups of the premod display are driven according to the OR-function of the premod versions of respective portions of the leading bitplane, the phased bitplane and the following bitplane, at least in the time period corresponding to the prime display being driven according to the phased bitplane.

20. A non-transitory computer-readable medium storing a computer program, wherein execution of the computer program is for:
at a projector comprising: a light source; a premod display; a prime display, the premod display configured to modulate light from the light source to illuminate the prime display, and a computing device, driving, using the computing device, the prime display according to a phased sequence to transition the prime display from a leading bitplane to a following bitplane; and,
at least in a time period corresponding to the prime display being driven according to the phased sequence, driving, using computing device, adjacent pixel groups of the premod display according to an OR-function of premod versions of respective portions of each of at least the leading bitplane and the following bitplane.

Assignees

• Christie Digital Systems Usa

Inventors

• Nicholson Stuart James Myron
• Goerzen Lawrence

Classifications

• H04N9/315

  Modulator illumination systems (general applications of lighting devices F21V; general optical systems G02B; lamp houses for projectors not peculiar to the presence of an electronic spatial light modulator G03B21/20) · CPC title

• H04N9/31 Primary

  Projection devices for colour picture display {, e.g. using electronic spatial light modulators [ESLM]} · CPC title

• G09G2320/0247

  Flicker reduction other than flicker reduction circuits used for single beam cathode-ray tubes · CPC title

• G09G2320/0653

  Controlling or limiting the speed of brightness adjustment of the illumination source · CPC title

• G09G2320/0646

  Modulation of illumination source brightness and image signal correlated to each other · CPC title