Patent ID: 6577285
Filing Date: 2003-06-10
Classification: G09G

Abstract:
A gamma corrector, comprising: an input inputting an image signal to a plurality of differential amplifiers which are connected in parallel to each other and an output mixing a plurality of output signals which are outputted from the differential amplifiers to output an image signal to which the gamma correction has been applied, wherein each of the differential amplifiers amplifies and outputs the inputted image signal with a different gain characteristic so that the gain characteristic of the signal obtained by mixing the output signals varies at two inflection points, wherein the plurality of differential amplifiers comprises:a first differential amplifier for amplifying the image signal with a constant gain; a second differential amplifier for amplifying the image signal with zero (0) or a positive gain when the image signal is smaller than a first set point; a third differential amplifier for amplifying the image signal with a negative gain when the image signal is larger than the first set point; and a fourth differential amplifier for amplifying the image signal with a negative gain when the image signal is smaller than a second set point.