Sony Corporation

Isao Umezawa

Haruo Sone

Kenji Shintani

Osamu Yoneyama

Tadahiro Kusuda

Toshihiko Minami

A semiconductor laser comprising a laser diode which is mounted on a semiconductor chip which has a monitoring photodiode formed therein so as to monitor the laser light output of the laser diode. The cathode of the laser diode and the anode of the monitoring photodiode are connected together, and a suitable forward voltage for the laser diode and reverse voltage for the monitor photodiode is provided by a single power supply which results in a simple construction of an output detection circuit for the monitor photodiode which produces an increased output over prior art devices.

Semiconductor laser chip

A photodetector includes a center photosensitive section having a surface for receipt of light reflected from an optical recording medium in producing information recorded on the optical recording medium. The center photosensitive section includes a plurality of photosensitive elements separated by a space from one another. A non-reflective transparent film is provided on substantially the whole area of the surface of the center photosensitive section to cover the photosensitive elements and the space.

Photodetector for use with an optical recording medium

A photosensor device and an optical pickup device incorporating the photosensor device are advantageously used in an optical compact disc player of the type where the optical pickup device is driven along a path at an acute tilt angle relative to the sides of a rectangular casing. The photosensor has a plurality of photosensitive elements aligned in a first direction and a plurality of terminal leads extending parallel to each other and perpendicular to a second direction so that the photosensor may be mounted on a circuit board in a conventional configuration to save space. Within the optical pickup device, the photosensitive elements are aligned at a mounting angle which is a function of the tilt angle so that the three optical beams are received thereon in the proper orientation.

Growing community of inventors

Kanagawa, Japan

Isao Umezawa