An image display apparatus, including: a light source which emits coherent light; a spatial modulation element which diffracts the coherent light by displaying a diffraction grating pattern corresponding to an input image and which displays a virtual image by the diffracted light; and a control unit which calculates a total brightness representing a sum total of brightnesses of all pixels of the input image, and controls at least one of the light source and the spatial modulation element in such a manner that, if the total brightness has decreased, the virtual image is displayed at a lower brightness than a reference virtual image displayed when the input image is used directly.