Hitachi, Ltd.

Shinji Ohyama

Masahiko Ibamoto

Nobuyoshi Tsuboi

Hiroyuki Minemura

Satoshi Shimada

Yoshio Sato

Hiroaki Koyanagi

Manabu Sato

Soshiro Kuzunuki

Tatsuki Inuzuka

Atsushi Kanke

Norifumi Miyamoto

Mitsunari Kano

Masahiro Takasaka

An optical recording sheet includes a plurality of data columns consisting of optical recording dots arranged in a matrix shape and column markers corresponding to the data columns. The data columns and the column markers of the optical recording sheet are detected by an optical line sensor and stored in a memory. On the basis of information stored in the memory, a marker detector detects the column marker and then two memory coordinates having a position known relative to the column marker are calculated. From the two memory coordinates, an inclining angle detector calculates the inclining angle between the optical recording sheet and the optical line sensor. On the basis of the memory coordinates and the inclining angle, an address calculator restores the optical recording dots stored in the memory coordinates.

Optical recording sheet and method and apparatus for reproducing the same

A waveguide path type optical pickup is provided for preventing a returning light from returning back to a light source. A filter for selectively allowing either Te polarized light or TM polarized light to pass through the filter is provided in an optical path from a light source to an optical path deflector. An optical part for changing the polarized state of light is provided in an optical path from the optical path changing part to an information recording medium, thereby prevent a reduction in S/N ratio or reproducing signal.

Optical element, optical disc and rotary encoder with the optical element

In a liquid crystal display combined with a signal input tablet of the type which includes a light source, a liquid crystal display disposed on the light source and a transparent tablet for detecting a planar write position by a hand-writing pen which tablet is disposed on the liquid crystal display, the present invention is characterized in that a two-dimensional lens array is disposed as one-to-one erect imaging optical system between the liquid crystal display and the transparent tablet so that the display image of the liquid crystal display is projected as the same size erect image on the surface of the transparent tablet having a light diffusion operation.

Liquid crystal display combined with signal input tablet

An optical head including a substrate, an optical waveguide formed on the substrate, a light source formed on a portion of the substrate, a collimator lens for converting light from the light source into parallel light rays, an objective lens for focusing light from the collimator lens onto a recording medium and for converting reflected light from the recording medium into parallel light rays, a beam splitter for dividing light from the objective lens into two parts to send out one of the parts in a predetermined direction, a coupling lens for focusing light from the beam splitter on a position, and a photodetector for detecting light from the coupling lens, is disclosed, in which the collimator lens, the objective lens, the beam splitter, the coupling lens and the photodetector are integrated on the substrate, and the collimator lens or an objective lens supporting part is made flexible to vary the position of the focus of the collimator lens or objective lens by piezo-electric elements.

Intergrated optical head with flexible substrate portion

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Hitachi, Japan

Shinji Ohyama