US Patent No. 10,490,137

BACKLIGHT BRIGHTNESS ADJUSTMENT METHOD AND APPARATUS


Patent No. 10,490,137
Issue Date November 26, 2019
Title Backlight Brightness Adjustment Method And Apparatus
Inventorship Huadong Fu, Guangdong (CN)
Zhe Huang, Guangdong (CN)
Assignee SHENZHEN SKYWORTH-RGB ELECTRONIC CO., LTD., Shenzhen (CN)

Claim of US Patent No. 10,490,137

2. A backlight brightness adjustment apparatus, wherein the apparatus comprises a processor and a memory coupled to the processor, the memory stores programmed instruction units executable by the processor and comprises:an acquiring module, configured to divide a backlight area of a liquid crystal display (LCD) into multiple sub-areas, acquire maximum pixel brightness M of each sub-area, and acquire average pixel brightness A according to the maximum pixel brightness M;
an adjustment module, configured to classify the brightness into multiple brightness ranges, and separately adjust duty cycles and drive currents of a backlight source in different brightness ranges according to the average pixel brightness A and the maximum pixel brightness M;
a determining module, configured to determine, according to the maximum pixel brightness M of each sub-area, a brightness range of the sub-area, and acquire an adjusted duty cycle and drive current that correspond to the brightness range of each sub-area; and
a control module, configured to correspondingly control illumination brightness of each sub-area by using the adjusted duty cycle and drive current;
wherein the brightness ranges comprise a first brightness range, a second brightness range, and a third brightness range; brightness in the first brightness range, the second brightness range, and the third brightness range progressively increases; and the adjustment module comprises:
a duty cycle adjustment unit, configured to adjust the duty cycles of the backlight source in the different brightness ranges according to the average pixel brightness A and the maximum pixel brightness M by using a first algorithm; and
a drive current adjustment unit, configured to adjust the drive currents of the backlight source in the different brightness ranges according to the average pixel brightness A, the maximum pixel brightness M, and a maximum drive current of the backlight source by using a second algorithm;
wherein, the drive current adjustment unit comprises:
a fourth adjustment subunit, configured to: in the first brightness range, set a first drive current I1 of the backlight source to be the maximum drive current I of the backlight source;
a fifth adjustment subunit, configured to: in the second brightness range, set a second drive current I2 of the backlight source to be equal to C1*I+f1(M, A), wherein C1 is a first current adjustment coefficient, 00; and
a sixth adjustment subunit, configured to: in the third brightness range, set a third drive current I3 of the backlight source to be equal to I+f2(M, A), wherein f2(M, A) is a function using the average pixel brightness A and the maximum pixel brightness M as variables, f2(M, A)?0.