Patent ID: 8199091

Claim:
A gamma voltage conversion device for generating a gamma driving voltage according to a gray level signal, the gray level signal and the gamma driving voltage are conformed to a first gamma curve or a second gamma curve, the gamma voltage conversion device comprising: a gamma voltage conversion circuit for generating a first gamma voltage according to the gray level signal, comprising: a first decoder for receiving the gray level signal so as to accordingly generate a plurality of first decoded signals; a first resistor series, coupled between a reference voltage source and a ground end, the first resistor series comprising a plurality of resistors connected in series; wherein each resistor of the plurality of the resistors of the first resistor series has a predetermined resistance and provides a corresponding resistor partial voltage according to the reference voltage source; a plurality of first switches, each of the plurality of the first switches comprises: a first end, coupled to a corresponding resistor of the plurality of the first resistor series, for receiving the corresponding resistor partial voltage provided by the corresponding resistor; a second end, coupled to the first input end of the operational amplifier; and a control end, coupled to the first decoder, for receiving a corresponding first decoded signal of the plurality of first decoded signals; wherein the first switch couples the first end of the first switch to the second end of the first switch according to the received first decoded signal so as to transmit the corresponding resistor partial voltage to the first input end of the operational amplifier; wherein a resistor partial voltage transmitted from one of the plurality of first switches to the operational amplifier is served as the first gamma voltage; wherein the gray level signal and the first gamma voltage are conformed to the first gamma curve; an operational amplifier, comprising: a first input end, coupled to the gamma voltage conversion circuit, for receiving the first gamma voltage; a second input end; and an output end; wherein the operational amplifier outputs the first gamma voltage or a second gamma voltage as the gamma driving voltage according to the first input end of the operational amplifier and the second input end of the operational amplifier; wherein the gray level signal and the second gamma voltage are conformed to the second gamma curve; and a gamma voltage adjusting circuit, coupled between the second input end of the operational amplifier and the output end of the operational amplifier, for controlling the operational amplifier outputting the first gamma voltage or the second gamma voltage as the gamma driving voltage according to the gray level signal and a gamma curve selection signal.