Image display device with reduced flickering and blur

• US 20060202945A1
• Filed: 06/20/2005
• Published: 09/14/2006
• Est. Priority Date: 03/09/2005
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Laboratories of America Incorporated (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Feng, Xiao-fan
• Granted Patent: US 8,115,728 B2
• Time in Patent Office: Days
• US Class Current: 345/102
• CPC Class Codes: G09G 2310/0237 Switching ON and OFF the backlight within one frame
• CPC Class Codes: G09G 2310/024 Scrolling of light from the illumination source over the display in combination with the scanning of the display screen
• CPC Class Codes: G09G 2310/08 Details of timing specific for flat panels, other than clock recovery
• CPC Class Codes: G09G 2320/0252 Improving the response speed
• CPC Class Codes: G09G 2320/0257 Reduction of after-image effects
• CPC Class Codes: G09G 2320/0261 in the context of movement of objects on the screen or movement of the observer relative to the screen
• CPC Class Codes: G09G 2320/0646 Modulation of illumination source brightness and image signal correlated to each other
• CPC Class Codes: G09G 2320/0666 for control of colour parameters, e.g. colour temperature
• CPC Class Codes: G09G 2320/103 Detection of image changes, e.g. determination of an index representative of the image change
• CPC Class Codes: G09G 2340/16 Determination of a pixel data signal depending on the signal applied in the previous frame
• CPC Class Codes: G09G 3/342 using several illumination sources separately controlled corresponding to different display panel areas, e.g. along one dimension such as lines
• CPC Class Codes: G09G 3/3426 the different display panel areas being distributed in two dimensions, e.g. matrix
• CPC Class Codes: G09G 3/3666 with the matrix divided into sections

Abstract

A backlit display with improved display characteristics.

Claims

1. A method for displaying an image on a liquid crystal display including a light valve comprising:

(a) receiving an image signal;

(b) providing light to said light value for a first region of said image based upon a determination that said first region is likely to include motion;

(c) providing light to said light value for a second region of said image based upon a determination that said second region is not likely to include motion.

2. The method of claim 1 wherein said determination includes estimating the amount of motion.

3. The method of claim 1 wherein said determination includes an estimation of a lack of motion.

4. The method of claim 1 wherein said first region corresponds to a plurality of light emitting elements and said second regions corresponds to a plurality of other light emitting elements.

5. A method for displaying an image on a display including a light valve comprising:

(a) receiving an image signal;

(b) providing light to a first pixel of said light valve having an illumination characteristic within a frame that is different from another pixel of said display during a frame.

6. The method of claim 5 wherein said illumination characteristic is based upon the said image signal.

7. The method of claim 5 wherein said illumination characteristic is primarily luminance.

8. The method of claim 5 wherein said illumination characteristic includes color.

9. The method of claim 5 wherein said illumination characteristic is provided to a region of said image based upon motion.

10. The method of claim 5 wherein said illumination characteristic is provided to a region of said image comprising a plurality of pixels.

11. The method of claim 10 wherein said illumination characteristic is provide to another region of said image comprising a plurality of pixels.

12. A method for displaying an image on a liquid crystal display including a light valve comprising:

(a) receiving an image signal;

(b) illuminating a backlight of said liquid crystal display including a set of spatially displaced independently controllable light emitting elements;

(c) selectively adjusting said light value to modify the luminance output of said display;

(d) wherein said illumination of said light emitting elements of said backlight is modulated at a rate greater than a frame rate of said display and said image signal is modified to provide a motion compensated image that is displayed with said image signal.

13. The method of claim 12 wherein said illumination is different during a frame for two different regions of said display.

14. The method of claim 13 wherein said illumination is based upon a determination of motion for one of said regions.

15. A method for displaying an image on a liquid crystal display comprising:

(a) illuminating a first plurality of pixels of a first region of said display at a non-zero illumination level during a first time period of said frame;

(b) illuminating a second plurality of pixels of a second region of said display at a non-zero illumination level during two different time periods of said frame with a lesser illumination level therebetween;

(c) wherein the total said illumination provided to said first plurality of pixels during said frame and the total said illumination provided to said first plurality of pixels is within 50% of each other.

16. The method of claim 15 wherein said total illuminations are within 25% of each other.

17. The method of claim 15 wherein said total illuminations are within 10% of each other.

18. The method of claim 15 wherein said total illuminations are substantially the same.

19. A method for displaying an image on a liquid crystal display comprising:

(a) illuminating a first plurality of pixels of said display over a plurality of frames at a first average rate;

(b) illuminating said first plurality of pixels of said display over another plurality of frames at a second average rate;

(c) illuminating said first plurality of pixels of said display for at least one frame between said plurality of frames and said another plurality of frames at a third average rate, when at least one frame of said first plurality of frames and said another plurality of frames is included, that is between said first and second average rates.

20. The method of claim 19 wherein said first plurality of pixels and said second plurality of pixels are different regions of said display wherein the luminance provided to said pixels is independently controllable.

21. The method of claim 19 wherein said first average rate is based upon a determination that said first plurality of pixels have been determined to have sufficient motion between frames.

22. The method of claim 21 wherein said second average rate is based upon a determination that said second plurality of pixels have been determined not to have sufficient motion between frames.

23. A method for displaying an image on a display including a light valve comprising:

(a) receiving an image signal;

(b) providing light to a first pixel of said light valve having an illumination characteristic within a frame that is modified by an overdrive based upon sufficient motion associated with said first pixel;

(c) providing light to another pixel of said light valve having an illumination characteristic within said frame that is not modified by said overdrive based upon insufficient motion associated with said another pixel.

24. A method for displaying an image on a display including a light valve comprising:

(a) receiving an image signal;

(b) determining a first group of pixels based upon a determination that said first group of pixels has sufficient motion

(c) providing light to a second group of pixels that includes said first group of pixels wherein part of said second group of pixels has insufficient motion;

(d) illuminating said second group of pixels of said light valve having an illumination characteristic within a frame that is different from another pixel of said display during a frame.