Hitachi, Ltd.

Hitachi Video and Information System, Inc.

Tatsumi Hasebe

Mikio Shiraishi

Junichi Ikoma

Yoshie Kodera

Sadayuki Nishimura

Makoto Iida

Hiroki Kuramoto

Akio Nakashima

Yoshihisa Hosoe

Akira Okamoto

Yoshimasa Takeuchi

Michiyuki Yoshino

Aki Nakajo

Hiroshi Oshima

Fusamitsu Tsubata

Sadayauki Nishimura

Yasutoshi Nakashima

A projection type image display device superior in reliability and also superior in both repairability and maintainability is to be provided at a low cost. Support members disposed between liquid crystal panels and a prism are made of a thermoplastic polymer material, and the liquid crystal panels and the support members are fixed to each other by heat-fusion of the support members. When it is necessary to remove a liquid crystal panel which is at fault for example from the corresponding support member, the fused portion on the support member side which less expensive is cut off, thereby permitting the liquid crystal panel which is expensive to be taken out re-utilizably without any damage thereto.

Projection type image display device

In a projector, the precision of color synthesis is improved and the generation of vertical stripes in the projected image is suppressed by a dichroic prism used for color synthesis that employs at least the following aspects. (1) The dichroic prism is formed using triangular prisms, in which projections or grooves are provided that have two faces parallel to two pasted faces of the triangular prisms, the projections or grooves being integrally injection-molded on faces of the triangular prisms that are substantially perpendicular to the light beam (i.e., the faces through which no light beam passes); (2) the dichroic prism is positioned using marks on the pasted faces of the triangular prisms; or (3) the dichroic prism is formed by engaging triangular prisms in which recesses or projections are formed.

Projector

There is provided the construction of a multiprojection apparatus composed of a plurality of projection units arranged in the vertical and horizontal directions, in which a transparent holding strip having an H-shaped cross section is inserted between screens each composed of a lenticular sheet and a Fresnel lens, and the right and left ends of a multiscreen are supported by elastic support members, or in which a receive member for receiving the screen in the direction of the optical axis and a screen holding device are provided, the receive member has such a shape as not to block projection light corresponding to an image on the screen and is located near a joint of the screen and another screen, and the holding device is disposed on a black stripe of the lenticular sheet and always pulled by an elastic member toward the receive member. Therefore, according to the present invention, it is possible to restrict the missing of information due to joints of the screens.

Multiprojection apparatus

Growing community of inventors

Hichiso, Japan

Tatsumi Hasebe