Other

Hitachi, Ltd.

Hitachi, Ltd., and Hitachi Video and Information Systems, Inc.

Takuya Shiaki

Masahiko Yatsu

Naohiro Ozawa

Takashi Kakuda

Yutaka Matsuda

Futoshi Yamasaki

Nobuyuki Kaku

Atsushi Ishibashi

Shigehisa Hagura

Yasuo Otsuka

Takeshi Hoshino

Takesuke Maruyama

Tomohiro Miyoshi

Kenji Fuse

Masaharu Deguchi

Satoshi Ohuchi

Makoto Fukatsu

Seiichi Sekiguchi

Mikiharu Kuwata

Nobuhiko Konuma

Hidetomo Yoshimura

Koichi Umezawa

Satoshi Ouchi

Satoshi Nakayama

Nobuyuki Kimura

Tsutomu Nakashima

Eiji Yamaguchi

A liquid crystal projector comprises an illuminating optical system including a light source, a color separating optical system for separating illuminating light rays emitted by the illuminating optical system into light rays of three colors, a projection lens unit comprising a projection lens, a cross dichroic prism disposed near a light receiving end of the projection lens, and a plurality of liquid crystal panels arranged around the cross dichroic prism, and a light source power supply for supplying power to the light source. The projection lens unit, the color separating optical system, the illuminating optical system and the light source power supply are arranged in that order. The liquid crystal projector has an outside size in a horizontal plane of 263 mm by 318 mm or below. The liquid crystal panels have a display screen size of 0.9 in. A cooling fan for cooling the plurality of liquid crystal panels is disposed beside the projection lens.

Liquid crystal projector, and projection lens unit, optical unit and cooling system for the same

A projection display according to the present invention reduces the size of a light beam in the optical path of an illumination optics from the periphery to change the amount of light incident on a video display device and the angle of such incidence, thereby making a plurality of image brightness/contrast combinations selectable. Further, the present invention changes the revolving speed of a projection display cooling fan and the adjustment value settings for the video display device's electrical characteristics in accordance with the aperture.

Projection display

A projection type liquid crystal display device, including: irradiation means having a function of irradiating light emitted from a light source upon an irradiated surface; a liquid crystal display element for modulating the light; and projection means for projecting the light emitted from said liquid crystal display element, wherein said irradiation means comprises: at least one reflection mirror; a polarization beam splitter for dividing the light from the light source into P polarization light and S polarization light; a &lgr;/2 phase shifting plate for rotating a direction of polarization of either one of the P polarization and S polarization lights; polarization means being constructed with a reflection mirror for reflecting either one of the P polarization and S polarization lights; a first lens array being constructed with a plurality of condenser lenses, for collecting the light emitted from said polarization means so as to form a plurality of secondary light source images; and a second lens array being constructed with a plurality of condenser lenses and positioned in vicinity of where the plurality of secondary light source images are formed.

Projection type liquid crystal display device

A projection type liquid crystal display device, including: irradiation means having a function of irradiating light emitted from a light source upon an irradiated surface; a liquid crystal display element for modulating the light; and projection means for projecting the light emitted from said liquid crystal display element, wherein said irradiation means comprises: at least one reflection mirror; a polarization beam splitter for dividing the light from the light source into P polarization light and S polarization light; a .lambda./2 phase shifting plate for rotating a direction of polarization of either one of the P polarization and S polarization lights; polarization means being constructed with a reflection mirror for reflecting either one of the P polarization and S polarization lights; a first lens array being constructed with a plurality of condenser lenses, for collecting the light emitted from said polarization means so as to form a plurality of secondary light source images; and a second lens array being constructed with a plurality of condenser lenses and positioned in vicinity of where the plurality of secondary light source images are formed.

Growing community of inventors

Sagamihara, Japan

Takuya Shiaki