CN-122029595-A - De-non-uniform tuning for 2D backlight systems

Abstract

A method for deskewing is provided. The method includes collecting a plurality of luminance maps of a plurality of light sources of a two-dimensional backlight system for a plurality of test patterns, each test pattern indicating each of the plurality of light sources to be turned on or off. Each of the plurality of light sources is turned on in only one test pattern of the plurality of test patterns. The plurality of luminance maps indicates luminance levels of the plurality of light sources for the plurality of test patterns. The method further includes generating an accumulated luminance map by adding the plurality of luminance maps together. The method further includes generating a de-skew compensation factor for the plurality of light sources based on the cumulative luminance map.

Inventors

• A. SHARMA
• Nai Shichong
• Furihata Hiroshi
• SUGIYAMA AKIO

Assignees

• 辛纳普蒂克斯公司

Dates

Publication Date

20260512

Application Date

20241011

Priority Date

20240808

Claims (20)

1. 1.A method, comprising: collecting a plurality of luminance maps of a plurality of light sources of a two-dimensional backlight system for a plurality of test patterns, each test pattern indicating each of the plurality of light sources to be turned on or off, each of the plurality of light sources being turned on in only one test pattern of the plurality of test patterns, wherein the plurality of luminance maps indicate luminance levels of the plurality of light sources for the plurality of test patterns; generating an accumulated luminance map by adding the plurality of luminance maps together, and A de-skew compensation factor for the plurality of light sources is generated based on the cumulative luminance map.
2. 2. The method of claim 1, wherein the plurality of test patterns includes a first test pattern in which a first group of the plurality of light sources is turned on and a first remaining group of the plurality of light sources is turned off, and Wherein each light source of the first set of light sources is adjacent to only light sources of the first remaining set of light sources.
3. 3. The method of claim 2, wherein the plurality of test patterns further comprises: A second test pattern, a second group of light sources of the plurality of light sources being turned on in the second test pattern; A third test pattern, a third group of light sources of the plurality of light sources being turned on in the third test pattern, and A fourth test pattern, a fourth group of light sources of the plurality of light sources being turned on in accordance with the fourth test pattern, Wherein the first, second, third and fourth sets of light sources do not share a light source.
4. 4. A method as claimed in claim 3, wherein each light source of the plurality of light sources belongs to one of the first, second, third and fourth sets of light sources.
5. 5. The method of claim 3, wherein the first set of light sources comprises a first light source, Wherein the second set of light sources comprises a second light source horizontally adjacent to the first light source, Wherein the third group of light sources comprises a third light source vertically adjacent to the first light source, and Wherein the fourth set of light sources comprises a fourth light source diagonally adjacent to the first light source.
6. 6. The method of claim 1, wherein acquiring the plurality of luminance maps of the plurality of light sources comprises: Capturing a plurality of images of a display panel while the display panel is illuminated by the plurality of light sources through the plurality of test patterns, and The plurality of luminance maps of the plurality of light sources are generated based on the plurality of images.
7. 7. The method of claim 1, further comprising generating a directional filter representative of light diffusing characteristics of the plurality of light sources, Wherein generating the de-skew compensation factor for the plurality of light sources is further based on the directional filter.
8. 8. The method of claim 7, wherein generating the directional filter comprises: collecting a first illuminance distribution for a fifth test pattern, two adjacent light sources of the plurality of light sources being turned on in the fifth test pattern; collecting a second illuminance distribution for a sixth test pattern, one of the two adjacent light sources being turned on in the sixth test pattern; collecting a third illuminance distribution for a seventh test pattern, the other of the two adjacent light sources being turned on in the seventh test pattern, and The directional filter is generated based on the first, second, and third illuminance distributions.
9. 9. The method of claim 7, wherein generating the de-skew compensation factor for the plurality of light sources comprises: Applying the de-non-uniform compensation factor and the directional filter to the accumulated luminance map to generate a compensated luminance map, and The de-skew compensation factor is modified based on the compensated luminance map.
10. 10. A calibration system, comprising: Processor, and A storage device configured to store computer-executable instructions that, when executed, cause the processor to: collecting a plurality of luminance maps of a plurality of light sources of a two-dimensional backlight system for a plurality of test patterns, each test pattern indicating each of the plurality of light sources to be turned on or off, each of the plurality of light sources being turned on in only one test pattern of the plurality of test patterns, wherein the plurality of luminance maps indicate luminance levels of the plurality of light sources for the plurality of test patterns; generating an accumulated luminance map by summing together the luminance maps, and A de-skew compensation factor for the plurality of light sources is generated based on the cumulative luminance map.
11. 11. The calibration system of claim 10, wherein the plurality of test patterns includes a first test pattern in which a first group of the plurality of light sources is turned on and a first remaining group of the plurality of light sources is turned off, and Wherein each light source of the first set of light sources is adjacent to only light sources of the first remaining set of light sources.
12. 12. The calibration system of claim 11, wherein the plurality of test patterns further comprises: A second test pattern, a second group of light sources of the plurality of light sources being turned on in the second test pattern; A third test pattern, a third group of light sources of the plurality of light sources being turned on in the third test pattern, and A fourth test pattern, a fourth group of light sources of the plurality of light sources being turned on in the fourth test pattern, and Wherein the first, second, third and fourth sets of light sources do not share a light source.
13. 13. The calibration system of claim 12, wherein the first set of light sources includes a first light source, Wherein the second set of light sources comprises a second light source horizontally adjacent to the first light source, Wherein the third group of light sources comprises a third light source vertically adjacent to the first light source, and Wherein the fourth set of light sources comprises a fourth light source diagonally adjacent to the first light source.
14. 14. The calibration system of claim 10, further comprising an imaging device configured to capture a plurality of images of the display panel while the display panel is illuminated by the plurality of light sources through the plurality of test patterns, Wherein acquiring the plurality of luminance maps of the plurality of light sources comprises generating the plurality of luminance maps of the plurality of light sources based on the plurality of images.
15. 15. The calibration system of claim 10, wherein the computer executable instructions, when executed, further cause the processor to generate a directional filter representative of light diffusion characteristics of the plurality of light sources, and Wherein generating the de-skew compensation factor for the plurality of light sources is further based on the directional filter.
16. 16. A non-transitory tangible computer-readable storage medium storing computer-executable instructions that, when executed, cause a processor to: collecting a plurality of luminance maps of a plurality of light sources of a two-dimensional backlight system for a plurality of test patterns, each test pattern indicating each of the plurality of light sources to be turned on or off, each of the plurality of light sources being turned on in only one test pattern of the plurality of test patterns, wherein the plurality of luminance maps indicate luminance levels of the plurality of light sources for the plurality of test patterns; generating an accumulated luminance map by summing together the luminance maps, and A de-skew compensation factor for the plurality of light sources is generated based on the cumulative luminance map.
17. 17. The non-transitory tangible computer-readable storage medium of claim 16, wherein the plurality of test patterns comprises a first test pattern in which a first group of light sources of the plurality of light sources is turned on and a first remaining group of light sources of the plurality of light sources is turned off, and Wherein each light source of the first set of light sources is adjacent to only light sources of the first remaining set of light sources.
18. 18. The non-transitory tangible computer readable storage medium of claim 17, wherein the plurality of test patterns further comprises: A second test pattern, a second group of light sources of the plurality of light sources being turned on in the second test pattern; A third test pattern, a third group of light sources of the plurality of light sources being turned on in the third test pattern, and A fourth test pattern, a fourth group of light sources of the plurality of light sources being turned on in accordance with the fourth test pattern, Wherein the first, second, third and fourth sets of light sources do not share a light source.
19. 19. The non-transitory tangible computer readable storage medium of claim 18, wherein the first set of light sources comprises a first light source, Wherein the second set of light sources comprises a second light source horizontally adjacent to the first light source, Wherein the third group of light sources comprises a third light source vertically adjacent to the first light source, and Wherein the fourth set of light sources comprises a fourth light source diagonally adjacent to the first light source.
20. 20. The non-transitory tangible computer readable storage medium of claim 16, wherein the computer executable instructions, when executed, further cause the processor to generate a directional filter representative of light diffusion characteristics of the plurality of light sources, and Wherein generating the de-skew compensation factor for the plurality of light sources is further based on the directional filter.

Description

De-non-uniform tuning for 2D backlight systems Cross reference to related applications The present application claims priority from U.S. patent application Ser. No. 18/798005, entitled "DEMURA TUNING FOR 2D BACKLIGHT SYSTEMS," filed 8/2024, and U.S. provisional patent application Ser. No. 63/590868, entitled "DEMURA TUNING FOR 2D BACKLIGHT SYSTEMS," filed 17/2023, which are incorporated herein by reference in their entireties. Technical Field The present disclosure relates generally to deskew (demura) tuning for two-dimensional (2D) backlight systems. Background The local dimming function based on a two-dimensional (2D) backlight is one of techniques for improving contrast of a Liquid Crystal Display (LCD) device. Local dimming techniques can achieve high dynamic contrast and low power consumption by individually controlling the respective light sources (e.g., light Emitting Diodes (LEDs)) of a 2D backlight system according to input image data. The image quality of the LCD device having the local dimming function may largely depend on the characteristics of the light source of the backlight system. In an LCD device having a local dimming function, one major problem is that luminance uniformity may be deteriorated due to a variation in optical characteristics of the corresponding light source. The de-unevenness function is a brightness compensation technique for improving brightness uniformity of an LCD device having a 2D backlight system. The de-skew function may function by applying a de-skew compensation factor to the luminance values of the respective light sources, wherein the de-skew compensation factor is determined based on the characteristics of the respective light sources. The de-skew compensation factor may be stored in the LCD device as de-skew data for correcting image non-uniformities in the LCD device. In some implementations, the deskew factors for the respective light sources may be determined during a tuning or calibration process of the LCD device. The tuning process may involve operating respective light sources of the 2D backlight system to illuminate the LCD panel according to a predetermined test pattern, and collecting luminance maps on the LCD panel for the respective test pattern. The de-skew compensation factor for the respective light source may be determined based on the acquired luminance map. Disclosure of Invention This summary is provided to introduce a selection of concepts in a simplified form that are further described below. This summary is not intended to necessarily identify key features or essential features of the disclosure. The present disclosure may include the following various aspects and embodiments. In an exemplary embodiment, the present disclosure provides a method. The method includes collecting a plurality of luminance maps of a plurality of light sources of a two-dimensional backlight system for a plurality of test patterns, each test pattern indicating each of the plurality of light sources to be turned on or off. Each of the plurality of light sources is turned on in only one test pattern of the plurality of test patterns. The plurality of luminance maps indicates luminance levels of the plurality of light sources for the plurality of test patterns. The method further includes generating an accumulated luminance map by adding the plurality of luminance maps together. The method further includes generating a de-skew compensation factor for the plurality of light sources based on the cumulative luminance map. In another exemplary embodiment, the present disclosure provides a calibration system including a processor and a storage device. The storage device is configured to store computer-executable instructions that, when executed, cause the processor to collect a plurality of luminance maps of a plurality of light sources of a two-dimensional backlight system for a plurality of test patterns, each test pattern indicating each of the plurality of light sources to be turned on or off. Each of the plurality of light sources is turned on in only one test pattern of the plurality of test patterns. The plurality of luminance maps indicates luminance levels of the plurality of light sources for the plurality of test patterns. The computer-executable instructions, when executed, further cause the processor to generate an accumulated luminance map by summing the luminance maps together and generate a de-skew compensation factor for the plurality of light sources based on the accumulated luminance map. In yet another exemplary embodiment, the present disclosure provides a non-transitory tangible computer-readable storage medium for non-uniformity calibration of a display device comprising a two-dimensional backlight system. The non-transitory tangible computer-readable storage medium stores computer-executable instructions that, when executed, cause a processor to collect a plurality of luminance maps of a plurality of light sources of a two-dimensional backlight s