Patent ID: 8421729
Filing Date: 2013-04-16
Classification: G09G

Abstract:
1. A liquid crystal display, comprising: a frequency converter that doubles a frame frequency of an input frame to generate a doubled odd numbered frame and a doubled even numbered frame; a timing controller that generates a gamma swing control signal, which controls a swing of a gamma reference voltage that is used for determining gray scale levels of the doubled odd numbered frame and the doubled even numbered frame; a gamma reference voltage generator that generates first gamma reference voltages having a different level corresponding to a high gray scale and second gamma reference voltages having a different level corresponding to a low gray scale, and the gamma reference voltage generator inversely swings the first gamma reference voltages of high gray scale and the second gamma reference voltages of low gray scale in accordance with the gamma swing control signal for a driving period of the doubled odd numbered frame and inversely swings the first gamma reference voltages of high gray scale and the second gamma reference voltages of low gray scale in accordance with the gamma swing control signal for a driving period of the doubled even numbered frame, and wherein the first gamma reference voltages of high gray scale and the second gamma reference voltages of low gray scale are inversely swung for driving periods of the doubled odd numbered frame and the doubled even numbered frame, wherein the gamma reference voltage generator includes a first switch that switching direction which is adjusted in accordance with a level of the gamma swing control signal from the timing controller, an inverter that inverts a level of the gamma swing control signal from the timing controller, a second switch that switching direction which is adjusted in accordance with a level of a gamma swing control signal which is inverted by the inverter, wherein the first and second gamma reference voltages are a voltage by which the a high-level power voltage and a ground voltage is dropped and divided by a plurality resistor, wherein the level of the first and second gamma reference voltages are swung by the gamma reference voltages which is switched via the first and second switch, wherein the timing controller supplies a gamma swing control signal having a low level to the gamma reference voltage generator for a driving period of the doubled odd numbered frame, and then supplies a gamma swing control signal having a high level to the gamma reference voltage generator for a driving period of the doubled even numbered frame, wherein the first gamma reference voltages are swung by the gamma reference voltages which is selectively output via the first switch, wherein the different low swing level of gamma reference voltages corresponding to a high gray scale, at the same time the second gamma reference voltages are swung by the gamma reference voltages which is selectively output via the second switch, wherein the different high swing level of gamma reference voltages corresponding to a low gray scale for the driving period of the doubled odd numbered frame, and wherein the first gamma reference voltages are swung by the gamma reference voltages which is selectively output via the first switch, wherein the different high swing level of gamma reference voltages corresponding to the high gray scale and, at the same time the second gamma reference voltages are swung by the gamma reference voltages which is selectively output via the second switch, wherein the different low swing level of gamma reference voltages corresponding to a low gray scale for the driving period of the doubled even numbered frame, wherein a level of the first gamma reference voltages are swung by the gamma reference voltages of two different levels which is switched via the first switch, and a levels of the second gamma reference voltages are swung by the gamma reference voltages of two different levels which is switched via the second switch, wherein the gamma reference voltages of two different levels which is switched via the first switch is dropped and divided by one of a first resistor, or wherein the gamma reference voltages of two different levels which is switched via the first switch is dropped and divided by one of a second resistor, wherein a realized gray scale level goes higher as a level of a gamma reference voltage is increased at a high gray scale, while a realized gray scale level goes lower as a level of a gamma reference voltage is decreased at a low gray scale, in a normally black mode.