Sharp Kabushiki Kaisha Corporation

Teruaki Inoue, Deceased

Toshiyuki Tanaka

Yukio Kurata

Yoshio Yoshida

Nobuo Ogata

Yasuo Nakata

Etsuji Minami

Hideaki Satou

A focusing error detector comprises a light source, a collimator lens for making parallel the pencil of rays emitted by the light source, an objective lens which focuses the parallel pencil of rays to form a beam spot on a data-recording disc with data tracks and guide tracks formed thereon and which receives the pencil of rays reflected from the data-recording disc, an optical system for forming a beam spot from the reflected pencil of rays incident to the objective lens, and an optical detector having a plurality of divided optical sensor blocks for receiving the formed beam spot so as to detect the focusing error of the beam spot formed on the data-recording disc on the basis of the configuration of the received beam spot.

Focusing error detector and optical data detecting device incorporating

Growing community of inventors

Nara, Japan

Teruaki Inoue, Deceased