System and method generating multi-color light for image display having a controller for temporally interleaving the first and second time intervals of directed first and second light beams

• US 8,129,669 B2
• Filed: 01/22/2008
• Issued: 03/06/2012
• Est. Priority Date: 01/22/2008
• Status: Expired due to Fees

• Current Assignee: Alcatel-Lucent SA (Nokia Corporation)
• Original Assignee: Alcatel-Lucent SA (Nokia Corporation)
• Inventors: Chen, Gang, Ryf, Roland
• Primary Examiner(s): LE, QUE TAN
• Application Number:
  US12/009,991
• Publication Number:
  US 20090185140A1
• Time in Patent Office: 1,505 Days
• Field of Search: 250/205, 250/208.1, 250/214.R, 353/85, 353/75, 353/31, 353/34, 348/798, 348744-758, 348800-802, 359887-892
• US Class Current: 250/205
• CPC Class Codes: G03B 21/2013 Plural light sources
• CPC Class Codes: G03B 21/2053 Intensity control of illuminating light controlled by video signal processing H04N5/74 or H04N9/31
• CPC Class Codes: H04N 9/3111 for displaying the colours sequentially, e.g. by using sequentially activated light sources sequential projection in colour photography G03B33/08
• CPC Class Codes: H04N 9/3155 for controlling the light source light source control per se H05B35/00 – H05B47/00; control of an illumination source for displays in general G09G3/3406
• CPC Class Codes: H04N 9/3164 using multiple light sources

Abstract

System including first and second light sources and controller. First light source is configured to generate first light beam of first perceived color. Second light source is configured to generate second light beam of different second perceived color. Controller is configured to direct light from first light beam to an image projector during first time intervals and to direct light from second light beam to an image projector during second time intervals. First light source generates first light beam with first intensity. Second light source generates second light beam with different second intensity. Controller is configured to temporally interleave first and second time intervals such that second time intervals are longer than first time intervals. Method also provided.

Claims

1. A system, comprising:

a first light source configured to generate a first light beam of a first perceived color;

a second light source configured to generate a second light beam of a different second perceived color; and

a controller configured to direct light from the first light beam to an image projector during first time intervals and to direct light from the second light beam to the image projector during second time intervals; and

wherein the first light source generates the first light beam with a first intensity, and the second light source generates the second light beam with a different second intensity; and

wherein the controller is configured to temporally interleave the first and second time intervals such that the second time intervals are longer than the first time intervals.

2. The system of claim 1, including an image projector, wherein the image projector is configured to display light from the first and second light beams such that, as displayed by the image projector, the second time intervals are longer than the first time intervals.

3. The system of claim 1, further including a third light source configured to generate a third light beam of a third perceived color, the third perceived color differing from the first and second perceived colors;

and

wherein the controller is configured to direct light from the third light beam to the image projector during third time intervals, the third time intervals being temporally interleaved between the first time intervals and between the second time intervals such that the third time intervals are shorter than the first and second time intervals.

4. The system of claim 3, wherein the third light beam has a third intensity that differs from the first intensity and differs from the second intensity.

5. The system of claim 3, wherein the first, second and third intensities, respectively integrated over the first, second and third time intervals, collectively produce a perceived color of white light.

6. The system of claim 3 wherein the controller is configured to simultaneously direct light from the first, second and third light beams to the image projector during fourth time intervals, the fourth time intervals following the third time intervals, and wherein the first, second and third intensities are selected to collectively produce a perceived color of white light.

7. The system of claim 1, wherein the second light source is configured for generating light within a wavelength range of between about 500 nanometers and about 550 nanometers.

8. The system of claim 1, wherein the controller is configured for pulsed operation of the first light source during the first time intervals.

9. The system of claim 8, wherein the controller is configured for generating a sub-period of the first time intervals when light from the first light source is directed to the image projector, having a different duration than another sub-period of the first time intervals when light from the first light source is not directed to the image projector.

19. The system of claim 1, wherein the first intensity is fixed at a substantially maximum output capability of the first light source and the second intensity is fixed at a substantially maximum output capability of the second light source.

20. The system of claim 1, wherein the controller is configured for computing lengths for the first time intervals as being quotients of a total full energy of the first perceived color to be displayed by the image projector, divided by the first intensity.

21. The system of claim 20, wherein the controller is configured for computing lengths for the second time intervals as being quotients of a total full energy of the second perceived color to be displayed by the image projector, divided by the second intensity;

and wherein the first intensity is fixed at a substantially maximum output capability of the first light source and the second intensity is fixed at a substantially maximum output capability of the second light source.

22. The system of claim 1, wherein the first intensity is fixed at a substantially maximum output capability of the first light source, wherein the second intensity is fixed at less than a substantially maximum output capability of the second light source, and wherein the second light source is configured for generating light having a green perceived color within a wavelength range of between about 500 nanometers and about 550 nanometers.

10. A method, comprising:

providing a first light source configured to generate a first light beam of a first perceived color, a second light source configured to generate a second light beam of a different second perceived color, and a controller configured to direct light from the first and second light beams to an image projector;

wherein the first light source generates the first light beam with a first intensity, and the second light source generates the second light beam with a different second intensity; and

causing the controller to direct light from the first light beam to the image projector during first time intervals, and to direct light from the second light beam to the image projector during second time intervals;

wherein causing the controller to direct light from the first and second light beams to the image projector includes causing the controller to temporally interleave the first and second time intervals such that the second time intervals are longer than the first time intervals.

11. The method of claim 10, including providing an image projector, and wherein causing the controller to direct light to the image projector includes causing the image projector to display light from the first and second light beams such that, as displayed by the image projector, the second time intervals are longer than the first time intervals.

12. The method of claim 10, including providing a third light source configured to generate a third light beam of a third perceived color, the third perceived color differing from the first and second perceived colors;

and wherein causing the controller to direct light includes causing the controller to direct light from the third light beam to the image projector during third time intervals, the third time intervals being temporally interleaved between the first time intervals and between the second time intervals such that the third time intervals are shorter than the first and second time intervals.

13. The method of claim 12, wherein the third light beam has a third intensity that differs from the first intensity and differs from the second intensity.

14. The method of claim 12, wherein the first, second and third intensities, respectively integrated over the first, second and third time intervals, collectively produce a perceived color of white light.

15. The method of claim 12, wherein causing the controller to direct light includes causing the controller to simultaneously direct light from the first, second and third light beams to the image projector during fourth time intervals, the fourth time intervals following the third time intervals, and wherein the first, second and third intensities are selected to collectively produce a perceived color of white light.

16. The method of claim 10, wherein the second light source is configured for generating light within a wavelength range of between about 500 nanometers and about 550 nanometers.

17. The method of claim 10, wherein causing the controller to direct light includes causing the controller to pulse emissions of light from the first light source during the first time intervals.

18. The method of claim 17, wherein causing the controller to pulse emissions of light includes causing the controller to generate a sub-period of the first time intervals when light from the first light source is directed to the image projector, having a different duration than another sub-period of the first time intervals when light from the first light source is not directed to the image projector.

23. The method of claim 10, wherein generating the first light beam includes fixing the first intensity at a substantially maximum output capability of the first light source;

and wherein generating the second light beam includes fixing the second intensity at a substantially maximum output capability of the second light source.

24. The method of claim 10, wherein causing the controller to direct light from the first light beam to the image projector includes computing lengths for the first time intervals as being quotients of a total full energy of the first perceived color to be displayed by the image projector, divided by the first intensity.

25. The method of claim 24, wherein causing the controller to direct light from the second light beam to the image projector includes computing lengths for the second time intervals as being quotients of a total full energy of the second perceived color to be displayed by the image projector, divided by the second intensity;

and wherein generating the first light beam includes fixing the first intensity at a substantially maximum output capability of the first light source; and

wherein generating the second light beam includes fixing the second intensity at a substantially maximum output capability of the second light source.

26. The method of claim 10, wherein generating the first light beam includes fixing the first intensity at a substantially maximum output capability of the first light source;

wherein generating the second light beam includes fixing the second intensity at less than a substantially maximum output capability of the second light source; and

wherein the second light source generates light having a green perceived color within a wavelength range of between about 500 nanometers and about 550 nanometers.