Cooling device for projection television

Abstract

Abstract PURPOSE:To reduce the reflectivity of a projector tube at the interface between the tube and a liquid for cooling the front surface of the tube so as to achieve increased image contrast, and prevent any breakage of the projector tube by using a specified liquid mixture of glycerol and ethylene glycol as the cooling liquid. CONSTITUTION:A cooling liquid (A) is poured through the hole 2i of a frame 2 into the space surrounded by a diaphragm 15, the projection surface of a projector tube 1 and the curved surface of a lens 1 to fill the space with the liquid (A). The cooling liquid (A) is a mixture of ethylene glycol and 20-40wt% of glycerol. Use of the cooling liquid (A) reduces a total reflectivity of the projector tube 1 and greatly increases the image contrast. Since the vapor pressure of glycerol is very small, it is possible to prevent any breakage of the projector tube 1 and a lens 11 resulting from pressure by making the vapor pressure of the cooling liquid (A) smaller than that of a conventional cooling liquid.

Inventors

• 👤 Shinichi Hasegawa
• 👤 伸一 長谷川

Bibliographic Details