Provided is a display device enhancing an image contrast ratio and thereby enhancing display quality without being affected by ambient brightness. The luminance of an image displayed on a first liquid crystal panel in a display gradually increases in slope as a gradation value increases from 0 to 255. Accordingly, luminance A for the gradation value 0 is the same as conventional luminance a for the gradation value 0. However, luminance B for the gradation value 255 is higher than conventional luminance 2b for that gradation value, resulting in a high contrast ratio as expressed by the following equation: B:A=B/A:1>2b/a:1.