Patent ID: 9024935
Filing Date: 2015-05-05
Classification: G09G

Abstract:
1. An image display apparatus, comprising: a normally white type liquid crystal panel; an input unit that receives an image signal; a drive unit that supplies a drive voltage in conformity with the image signal received by the input unit to the liquid crystal panel to display an image represented by the image signal on the liquid crystal panel; a detection unit that detects a histogram representing a relationship between a signal level of the image signal received by the input unit and a number of pixels; a calculation unit that calculates, based on the histogram detected by the detection unit, a first proportion of a number of pixels whose signal level is equal to or greater than a predetermined first defined value, to a total number of pixels of the histogram, and a second proportion of a number of pixels whose signal level is equal to or smaller than a second defined value that is smaller than the first defined value, to the total number of pixels of the histogram; and a correction unit that corrects a lower limit of the drive voltage that the drive unit supplies to the liquid crystal panel in accordance with the first proportion and second proportion calculated by the calculation unit, wherein the first proportion of the number of pixels includes a proportion of white side pixels to the total number of the pixels of the image histogram, wherein the second proportion of the number of pixels includes a proportion of black side pixels to the total number of the pixels of the image histogram, and wherein, after the correction unit corrects the lower limit of the drive voltage to fall at a predetermined value, and the proportion of black side pixels becomes zero, the correction unit gradually reduces the lower limit of the drive voltage.