System and method for color-specific sequence scaling for sequential color systems

• US 8,493,288 B2
• Filed: 10/10/2006
• Issued: 07/23/2013
• Est. Priority Date: 10/10/2006
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Dickinson, Larry D.
• Primary Examiner(s): Eisen, Alexander
• Assistant Examiner(s): MARINELLI, PATRICK
• Application Number:
  US11/545,436
• Publication Number:
  US 20080084369A1
• Time in Patent Office: 2,478 Days
• Field of Search: 345/84, 345/72, 345/108, 345/32, 345 87-104, 345204-215, 345690-699, 359/45, 359/449, 359/249, 359/298, 359/290, 359/315, 359/318, 359/224, 348/743, 348/771, 348/756
• US Class Current: 345/32
• CPC Class Codes: G09G 2310/0235 Field-sequential colour display
• CPC Class Codes: G09G 2320/062 Adjustment of illumination source parameters
• CPC Class Codes: G09G 2360/145 the light originating from the display screen
• CPC Class Codes: G09G 2360/16 Calculation or use of calculated indices related to luminance levels in display data
• CPC Class Codes: G09G 3/3413 Details of control of colour illumination sources

Abstract

System and method for adjusting the color segment durations for colors in a color sequence in sequential color display systems. A preferred embodiment comprises receiving a desired color sequence to display, computing a scaling factor for each color in the desired color sequence based on a reference color sequence, and sequentially displaying the colors in the desired color sequence. The reference color sequence used in computing the scaling factors specifies a duration for each color in the reference color sequence, while the desired color sequence specifies a desired duration for each color in the desired color sequence. The use of a single reference color sequence to create a large number of color sequences can save a significant amount of storage space and can allow for the storage of reference color sequences to meet varying chromatic properties due to changes in the display system, user settings, and operating environment.

Claims

1. A method for displaying a color sequence, using color-specific sequence scaling to compensate for variations in light output of different color light sources, comprising:

providing a reference color sequence for display of an image using light from the respective different color light sources, wherein the reference color sequence specifies a reference duration for each color in the reference color sequence for a reference light output of each corresponding color light source, and wherein the reference color sequence is determined based on bit weight and chromatic characteristics information, and information derived from received image data;

computing a color-specific scaling factor for each color in the reference color sequence for an actual light output of the corresponding color light source; and

controlling the operation of the color light sources to sequentially display each color in the color sequence based on the reference color sequence scaled by the computed scaling factor for each respective color.

2. The method of claim 1, wherein the reference color sequence is provided by retrieving a prestored color sequence from memory.

3. The method of claim 2, further comprising sensing the light output of the different light sources, and determining the actual light output from the sensed light output.

4. The method of claim 3, wherein the reference duration for each color is a display time greater or equal to a minimum display time, and the color-specific scaling factor is a factor that does not reduce a display time to less than the minimum display time.

5. The method of claim 4, wherein each color is displayed by sequentially illuminating a spatial light modulator having an array of light modulators, individual modulators of which assume states in synchronism with the different color illuminations based on settings derived from the image data.

6. The method of claim 5, wherein the spatial light modulator is a digital micromirror device, and the modulators are micromirrors.

7. The method of claim 6, wherein the color-specific scaling factor is a clock drop factor, and the reference color sequence is scaled using clock dropping.

8. The method of claim 7, further comprising storing the computed color-specific scaling factor in a memory.

9. The method of claim 1, wherein the reference duration for each color is a minimum display time, and the color-specific scaling factor is a factor greater than or equal to one.

10. The method of claim 1, wherein the reference duration for each color is a nominal display time greater than a minimum display time, and the color-specific scaling factor is a factor greater or less than one, that does not reduce a display time to less than the minimum display time.

11. The method of claim 1, wherein the reference color sequence is provided by retrieving a prestored color sequence from a memory.

12. The method of claim 1, further comprising sensing the light output of the different light sources, and determining the actual light output from the sensed light output.

13. The method of claim 1, further comprising storing the computed color-specific scaling factor in a memory.

14. The method of claim 1, wherein the color-specific scaling factor is a clock drop factor, and the reference color sequence is scaled using includes clock dropping.

15. The method of claim 1, wherein each color is displayed by sequentially illuminating a spatial light modulator having an array of light modulators, individual modulators of which assume states in synchronism with the different color illuminations based on settings derived from the image data.

16. The method of claim 15, wherein the spatial light modulator is a digital micromirror device, and the modulators are micromirrors.