Patent ID: 8289262

Claim:
A liquid crystal display (LCD) comprising: an LCD panel comprising a substrate and a shift register device, the shift register device being directly disposed on the substrate and has a plurality of shift registers connected in series for sequentially driving a plurality of pixel-rows of the LCD panel, an i th shift register of the plurality of shift registers comprising: a pre-charge unit receiving a first scan signal output by an (iâˆ’1) th shift register of the plurality of shift registers, and outputting a charge signal according to the first scan signal, where i is a positive integer; a pull-up unit coupled to the pre-charge unit, receiving the charge signal and a first clock signal, and outputting a second scan signal according to the charge signal and the first clock signal; and a pull-down unit coupled to the pre-charge unit and the pull-up unit, receiving a second clock signal and a third scan signal output by an (i+1) th shift register of the plurality of shift registers, and determining whether pulling down the second scan signal to a reference voltage according to the second clock signal and the third scan signal, wherein the pre-charge unit, the pull-up unit and the pull-down unit respectively have at least a transistor, the transistor in the pull-down unit has a first channel length, the transistors in the pre-charge unit and the pull-up unit respectively have a second channel length, the first channel length is greater than the second channel length, and first channel length is substantially 1.01 to 4 times the second channel length; and a backlight module providing a backlight source to the LCD panel.