Patent ID: 8040316
Filing Date: 2011-10-18
Classification: G02F,G03B

Abstract:
1. A display device, comprising: a liquid crystal panel that holds a layer of liquid crystal between substrates; a first diffraction grating which has a first diffraction method in which a light beam incident to the liquid crystal panel is diffracted in a predetermined direction; a second diffraction grating which has a second diffraction method, which is different from the first diffraction method, in which a light beam incident to the liquid crystal panel is scattered, with the first diffraction grating and the second diffraction grating being arranged in different regions respectively of the layer of liquid crystal; a light source that emits an illumination light onto a side of the liquid crystal panel; and a controller that controls the liquid crystal panel and the light source to alternately repeat first and second display states, wherein: in the first display state, the controller turns on the light source, controls the first diffraction grating to diffract the illumination light beam from the light source, and controls the second diffraction grating not to scatter the illumination light beam so that the first diffraction grating is illuminated whereas in the second display state, the controller turns off the light source, controls the first diffraction grating not to diffract the light beam incident to the liquid crystal panel, and controls the second diffraction grating to scatter the light beam incident to the liquid crystal panel so that the second diffraction grating is darkened.