Hitachi, Ltd.

Hitachi-lg Data Storage, Inc.

Hitachi Media Electronics Co., Ltd.

Nobuhiro Konuma

Yutaka Matsuda

Hiroki Yoshikawa

Kyohei Fukuda

Masaharu Deguchi

Takashi Kakuda

Masayuki Muranaka

Hiroshi Jitsukata

Isao Yoshizaki

Hisao Inage

Koji Hirata

Kenichi Shimada

Kunikazu Ohnishi

Tetsu Ohishi

Kenji Sato

Yasuo Amano

Takahiko Yoshida

Masaki Yoshii

Michio Hatagi

Takahoko Yoshida

Masakuni Teratani

An optical scanning device includes a rotationally-moving mirror on which a reflection plane is provided in a rotationally-movable manner, and a sealing unit over which a light-transmissive cover is provided, a first plane of the light-transmissive cover, a second plane of the light-transmissive cover, and the reflection plane of the rotationally-moving mirror within a rotationally-moving range being non-parallel to each other, the first plane being on the opposite side to the side of the rotationally-moving mirror, the second plane being on the side of the rotationally-moving mirror.

Optical scanning device and image display apparatus

An optical pickup for writing information to and/or for reading information from an optical disc having at least two recording layers (dual layer) provided with first and second recording layers can prevent layer crosstalk resulting from disturbing a signal reproduced from the first recording layer by a reflected light beam reflected from the second recording layer during a writing operation for writing information to the first recording layer or a reading operation for reading information from the fist recording layer. An orthogonal polarization region forming component forms an orthogonal polarization region, in which respective directions of polarization of a first light beam focused on and reflected by a first recording layer of an optical disc and a second light beam reflected by a second recording layer of the optical disc are perpendicular to each other, in a region, in which the first and the second light beam overlap each other, on a light-receiving surface of a detector. The orthogonal polarization region forming component is a polarization switch for changing the directions of polarization of part or all of the first and the second light beam.

Optical pickup and optical disc drive

A liquid crystal projector, having a configuration in which an exhaust fan is arranged adjacently to a projection lens at an angle to the optical axis of the projection lens, a configuration including a plurality of tilted wind-directing plates, a configuration in which the arrangement of a first reflection mirror, a first lens array, a light source and the exhaust fan is substantially parallel and adjacent to the arrangement of the projection lens, a dichroic prism and a second dichroic mirror, and/or a configuration in which the lens array has the incident surface thereof made of a concave lens.

Liquid crystal projector

In a liquid crystal projector using a reflective and scattering or reflective type liquid crystal panel, a plurality of light sources are used, thereby securing sufficient brightness of an image, increasing the F-number of a projection lens, and miniaturizing and lightening the projector. A light source is arranged right next to the projection lens and an exhaust port is arranged on the front face of the projector, thereby preventing hot heat discharged from the exhaust port from being discharged toward peripheral equipment or the operator.

In a polarization transforming optics having a polarizing beam splitter (PBS) for transforming x-direction incident light flux from a metal halide light source into a single linearly (z direction) polarized light flux beam heading in the y direction and delivering the beam to, preferably, a light valve of a liquid crystal display (LCD) in a coordinate space, the PBS splits the incident light flux from the light source into split light flux beams, separates the split light flux beams into linearly polarized light flux beams having polarizing directions which are orthogonal to each other, and delivers two linearly polarized outgoing light flux beams having polarizing directions which are orthogonal to each other and heading in directions parallel to a polarizing direction plane. One of the two outgoing light flux beams is deflected by a single mirror to have the same heading direction and polarizing direction as those of the other. The PBS is constructed by jointing together, for example, a quadrangular pyramidal prism and two triangular pyramidal prisms. A PBS film is formed at each joint interface and a surface in contact with air of each prism acts as a total reflection mirror surface. No wave plate is used to provide a compact apparatus having a high light utilization efficiency.

Polarization transforming optics, polarizing beam splitter and liquid

A projection lens system for a projection type television having a cathode-ray tube with a panel having a fluorescent inner surface for projecting an image onto a screen. The projection lens system includes a plurality of lens groups, the lens group positioned at a side nearest to the cathode-ray tube including, in successive order from a side toward the screen, a lens having a concave surface on the screenn side a transparent medium, and the cathode-ray tube panel having a fluorescent inner surface, the lens group attenuating at least a part of a wavelength region of the light emitted on the fluorescent surface so as to improve contrast while reducing observance of a ghost image due to multiple reflection without substantial impairment in at least one of brightness and luminance. More particularly, the attenuation is provided by the concave lens having at least one surface dyed in a predetermined color.

Projection lens system for projection type television

A projection-type stereoscopic image display system is disclosed in which a left-eye projection light ray and a right-eye projection light ray are projected from behind a transparent screen thereby to display a stereoscopic image.

Projection type stereoscopic image display system

A rear projection screen for use in a rear projection image display device comprises one or more sheet members through which light is sequentially transmitted from the side of a plane of incidence of the screen, the last sheet member comprising a transparent material as a base thereof, and a light diffusing layer provided on the side of a plane of emergence of the base. A light diffuser having a refractive index different from that of the base may be dispersed in the base so as to contrive a greater viewing angle. Further, a transperent binder for supporting the light diffuser dispersed in the light diffusing layer or the light diffuser itself may be colored in order to obtain a further enhanced contrast.

Growing community of inventors

Yokohama, Japan

Nobuhiro Konuma