The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 26, 1990
Filed:
Feb. 02, 1988
Satoshi Shimada, Hitachi, JP;
Shinji Ohyama, Hitachi, JP;
Manabu Sato, Hitachi, JP;
Masahiko Ibamoto, Katsuta, JP;
Yoshio Sato, Hitachi, JP;
Nobuyoshi Tsuboi, Naka, JP;
Norifumi Miyamoto, Hitachi, JP;
Hiroyuki Minemura, Hitachi, JP;
Hiroaki Koyanagi, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
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.