Projection type liquid crystal display device

Abstract

Abstract PURPOSE:To uniformize the contrast of the images over the entire surface of the screen by refracting the light from a light source in the optimum visual field angle direction where the contrast increases with respect to the normal of the liquid crystal display element by an optical path refracting means. CONSTITUTION:The ray 28 entering at an incident angle theta with the normal within one plane inclusive of the normal perpendicular to the liquid crystal layer of the liquid crystal display element 7 and the optimum visual field angle direction where the contrast is maximized is so refracted by the incident side optical path refracting means 25, such as prism, as to emit near the max. visual field angle direction to the above-mentioned normal at the angle (theta+alpha) larger than the angle position of the max. visual field angle direction and the ray 27 entering at an incident angle -theta is so refracted as to emit at the angle (-theta+alpha) on the side opposite to the max. visual field angle direction to the normal and near the normal. The exit light is again refracted by the optical path refracting means 26 on the exit side of the liquid crystal display element 7 to the direction where the exit light is nearly parallel with the incident light. The contrast is uniformized over the entire screen surface in this way.

Inventors

• 👤 Hiroshi Oka
• 👤 岡　博史
• 👤 Yutaka Takato
• 👤 裕 高藤

Bibliographic Details