Patent ID: 7535448

Claim:
A method of driving a liquid crystal display device comprising: supplying picture signals from a digital video data dividing circuit to a D/A converter circuit; supplying a first voltage for a first gradation from the D/A converter circuit to a pixel by first scanning signals of a gate driver in a first subframe period; supplying a voltage for a 0th gradation from the D/A converter circuit to the pixel by second scanning signals of the gate driver in a second subframe period after the first subframe period; supplying a second voltage for a second gradation from the D/A converter circuit to the pixel by third scanning signals of the gate driver in a third subframe period after the second subframe period; supplying a third voltage for a third gradation from the D/A converter circuit to the pixel by fourth scanning signals of the gate driver in a fourth subframe period after the third subframe period; displaying a first combined gradation in a first frame period comprising the first subframe period and the second subframe period; displaying a second combined gradation in a second frame period comprising the third subframe period and the fourth subframe period, and wherein the first subframe period and the second subframe period are adjacent to each other; wherein the third subframe period and the fourth subframe period are adjacent to each other; wherein in the first frame period the first combined gradation acknowledged by operator's eye is displayed; wherein the first combined gradation corresponds to half of the first voltage, wherein in the second frame period the second combined gradation acknowledged by operator's eye is displayed, wherein the second combined gradation corresponds to the second voltage and the third voltage, and wherein the voltage for the 0th gradation is for displaying black-display in a screen of the liquid crystal display device, wherein the second voltage is higher than the third voltage, wherein the first voltage and the second voltage are same voltage, and wherein the 0th gradation voltage is lower than the third voltage.