Hitachi, Ltd.

Keiichiro Tokushige

Takeshi Katayama

Tatsuo Morita

Hideharu Saito

Mikio Shiraishi

Hideki Okuyama

Reduction of noise is achieved by devising an arrangement of heat generating parts such as a light valve element, an electric power source, a light source, etc. and an arrangement of cooling fans. In cooling the light source, the electric power source and liquid crystal panels, a cooling wind path for the liquid crystal panels and the electric power source is made separate from and independent of a cooling wind path for the light source that generates much heat, a cooling air volume is optimized for the respective cooling wind paths, and noise accompanying the rotation of the cooling fans is reduced. Also, by arranging the cooling fans substantially centrally of the respective cooling wind paths, that volume of noise, which leaks from air intake ports and air exhaust port that are opened to a housing of a unit, is reduced.

Projection type display unit

A simple cooling construction capable of achieving two functions at a time is to be provided, one function being cooling a lamp as a lighting means and the other function being preventing the scatter of broken pieces of the lamp upon burst of the lamp. An image display device such as an LCD projector has been configured such that cooling air is introduced into the interior of a reflector to cool an lamp means. In this connection, the present invention adopts a net of an expanded metal structure which serves as both means for preventing the scatter of broken pieces of a lamp upon burst of the lamp and an air deflecting plate facing a portion to be cooled. The above two functions can be attained simultaneously by such a simple construction.

Growing community of inventors

Fujisawa, Japan

Keiichiro Tokushige