1. A liquid crystal display device including a liquid crystal drive device for operating liquid crystal according to an input video signal inputted in the liquid crystal display device, comprising: a gray scale conversion means, which, if the input video signal conveying a gray scale value belonging to a low gray scale region, converts the gray scale value of the input video signal to a gray scale value belonging to a high gray scale region, and outputs the video signal having the converted gray scale value to the liquid crystal drive device, where the low gray scale region is one of two regions into which a range of possible gray scale values are divided and to which gray scale values that cause the liquid crystal display device to display at low luminance are belonged, and the high gray scale region is the other one of the two regions to which gray scale values that cause the display device to display at high luminance are belonged.