US 12,307,985 B2
Liquid crystal display devices and backlight driving methods thereof based on preset expression with respect to average and maximum brightness values
Yizhuo Zhao, Guangdong (CN)
Assigned to TCL CHINA STAR OPTOELECTRONICS TECHNOLOGY CO., LTD., Shenzhen (CN)
Filed by TCL CHINA STAR OPTOELECTRONICS TECHNOLOGY CO., LTD., Guangdong (CN)
Filed on Nov. 15, 2023, as Appl. No. 18/509,362.
Claims priority of application No. 202311055410.1 (CN), filed on Aug. 18, 2023.
Prior Publication US 2025/0061863 A1, Feb. 20, 2025
Int. Cl. G09G 3/34 (2006.01); G09G 3/36 (2006.01)
CPC G09G 3/3406 (2013.01) [G09G 3/36 (2013.01); G09G 2320/0626 (2013.01); G09G 2360/16 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A liquid crystal display device, comprising:
a display panel comprising a plurality of display partitions, wherein each of the display partitions has a partition maximum brightness value and a partition average brightness value under each frame display image; and
a backlight module comprising:
a light-emitting unit comprising a plurality of backlight partitions corresponding to the display partitions, wherein each of the backlight partitions has a preset backlight brightness value under each frame display image, the preset backlight brightness value under a current frame display image is defined as a first preset backlight brightness value, and the preset backlight brightness value under a previous frame display image is defined as a second preset backlight brightness value;
a first processor, defined as a calculation unit, configured to calculate the first preset backlight brightness value of each backlight partition of the backlight partitions according to the partition average brightness value, the partition maximum brightness value, a first preset weight value corresponding to the partition maximum brightness value, and a second preset weight value corresponding to the partition average brightness value;
a second processor, defined as a comparison unit, configured to compare the second preset backlight brightness value of each backlight partition and the first preset backlight brightness value, and configured to output a comparison result; and
a third processor, defined as a control unit, configured to output a first brightness driving value of the backlight partition under the current frame display image according to the comparison result, and configured to control the light-emitting unit to emit light in the backlight partition according to the first brightness driving value;
wherein the control unit is further configured to output the first brightness driving value according to the partition maximum brightness value, a first driving weight value corresponding to the partition maximum brightness value, the partition average brightness value, and a second driving weight value corresponding to the partition average brightness value;
the first driving weight value is determined according to the first preset weight value and a third driving weight value corresponding to the partition maximum brightness value of the backlight partition under the previous frame display image, and the second driving weight value is determined according to the second preset weight value and a fourth driving weight value corresponding to the partition average brightness value of the backlight partition under the previous frame display image; and
when the comparison result is that the first preset backlight brightness value and the second preset backlight brightness value are different, the control unit is further configured to judge whether an average grayscale value under the current frame display image is less than a first preset threshold value and whether a maximum backlight grayscale value of all of the backlight partitions under the current frame display image is less than a second preset threshold value, and the control unit is configured to determine the first preset weight value as the first driving weight value and determine the second preset weight value as the second driving weight value when a judgment result is not satisfied.