Patent ID: 9460647
Filing Date: 2016-10-04
CPC Classification: G02B,G03H,G09G

Claim Text:
1. An image display apparatus, comprising: 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; 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; and a light shielding section which shields a portion of light emitted from the spatial modulation element, wherein the control unit adds a light shielding pattern to the image, the light shielding pattern generates light directed towards the light shielding section and includes an image different from the input image, and the control unit controls the spatial modulation element so as to display a diffraction grating pattern corresponding to the input image to which the light shielding pattern has been added.