Display Brightness Adjustment

• US 20130321369A1
• Filed: 05/30/2013
• Published: 12/05/2013
• Est. Priority Date: 05/31/2012
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Mirski-Fitton, Alexander D. S., Moffatt, Edwin P. J., Pilot, Richard W.
• Granted Patent: US 9,412,296 B2
• Time in Patent Office: Days
• US Class Current: 345/207
• CPC Class Codes: G09G 2320/0233 Improving the luminance or brightness uniformity across the screen
• CPC Class Codes: G09G 2320/0285 using tables for spatial correction of display data
• CPC Class Codes: G09G 2360/144 the light being ambient light
• CPC Class Codes: G09G 3/3208 organic, e.g. using organic light-emitting diodes [OLED]
• CPC Class Codes: G09G 3/3225 using an active matrix

Abstract

A display comprising an array of pixels having individually adjustable brightness levels; an array of light sensors fixed relative to the pixel array; and a brightness controller for estimating a glare footprint on the pixel array from light level data provided by the sensor array and for adjusting the relative brightness levels of pixels that fall in the estimated glare footprint.

Claims

1. A display comprising:

an array of pixels having individually adjustable brightness levels;

an array of light sensors fixed relative to the pixel array; and

a brightness controller for estimating a glare footprint on the pixel array from light level data provided by the sensor array and for adjusting the relative brightness levels of pixels that fall in the estimated glare footprint.

2. The display according to claim 1 wherein the array of light sensors extends around the display.

3. The display according to claim 1 wherein the array of light sensors is at least one of:

a single circuit of light sensors one sensor thick;

two circuits of light sensors;

three circuits of light sensors thick; and

more than three circuits of light sensors.

4. The display according to claim 1 further comprising means for estimating the footprint that traverses the sensors to identify locations where light level changes by a threshold amount and fits a footprint shape with three or more edges bounded by edges of the pixel array and at least one line connecting two identified locations in the senor array.

5. The display according to claim 1 wherein the threshold of light level change depends on a difference between the maximum and minimum light levels detected by the sensors.

6. The display according to claim 5 wherein the threshold of light level change is user configurable.

7. The display according to claim 1 wherein the increase in brightness level of a pixel is based on an estimated amount of light falling at the pixel location.

8. The display according to claim 1 wherein the increase in brightness levels of a pixel is user adjustable.

9. The display according to claim 1 wherein the display having pixels with individually adjustable brightness levels is an active matrix organic light emitting diode (AMOLED) displays whereby pixels in the “

light”

areas can have their brightness and contrast raised and/or pixels in the “

dark”

areas may have theirs lowered.

10. The display according to claim 1 wherein the amount of light falling is estimated as uniform over a single footprint and may be different for two or more footprints over the array and may be higher for overlapping footprint areas.

11. A method for controlling brightness of a display, said display comprising an array of pixels having individually adjustable brightness levels and an array of light sensors fixed relative to the pixel array, said method comprising:

estimating a glare footprint on the pixel array from light level data provided by the sensor array; and

adjusting the relative brightness levels of pixels that fall in the estimated glare footprint.

12. The method according to claim 11 wherein the array of light sensors extends around the display.

13. The method according to claim 11 wherein the array of light sensors is at least one of:

a single circuit of light sensors one sensor thick;

two circuits of light sensors;

three circuits of light sensors thick; and

more than three circuits of light sensors.

14. The method according to claim 11 comprising traversing the sensors to identify locations where light level changes by a threshold amount and fits a footprint shape with three or more edges bounded by edges of the pixel array and at least one line connecting two identified locations in the senor array.

15. The method according to claim 11 wherein the threshold of light level change depends on a difference between the maximum and minimum light levels detected by the sensors.

16. The method according to claim 15 wherein the threshold of light level change is user configurable.

17. The method according to claim 11 wherein the increase in brightness level of a pixel is based on an estimated amount of light falling at the pixel location.

18. The method according to claim 11 wherein the increase in brightness levels of a pixel is user adjustable.

19. A computer program product for controlling brightness of a display, said computer program product comprising computer readable recording medium having computer readable code stored thereon for performing the method of claim 11.

20. A computer program stored on a computer readable medium and loadable into the internal memory of a data processing system, comprising software code portions, when said computer program is run on the data processing system, for performing the method of claim 11.