In the image display device, the vignetting pattern generator generates a vignetting pattern image composed of image data having inverted brightness characteristics obtained by inverting brightness characteristics of a panel of the liquid crystal display. The display controller carries out control to cause a pattern image obtained by combining a flat pattern image in gray composed of image data having a uniform grayscale level and the vignetting pattern image to be displayed on the liquid crystal display. And the correction data calculator calculates correction data for correcting brightness unevenness of an input image based on brightness values of image data of captured images obtained by imaging, by the camera, the pattern images displayed on the liquid crystal display.