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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.:

US 4843604 B1

PDFFull Text
Date of Patent:
Jun. 27, 1989

Filed:

Oct. 16, 1986

Beam controller for magneto-optical disc memory system

Applicant:
Inventors:

Tetsuo Fujiwara, Tenri, JP;

Hiroshi Fuji, Tenri, JP;

Takashi Iwaki, Tenri, JP;

Toshihisa Deguchi, Nara, JP;

Shozou Kobayashi, Nara, JP;

Assignee:

Sharp Kabushiki Kaisha, Osaka, JP;

Attorney:

Birch, Stewart, Kolasch & Birch

Primary Examiner:

Alan Faber

Assistant Examiner:

Hoa T Nguyen

Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
369116 ; 369106 ; 369 13 ; 250205 ;
Abstract

A beam controller for controlling a semiconductor laser included in an optical recording-play-back apparatus. The beam controller is comprised of first and second current sources for driving the semiconductor laser at a low level during a play-back mode and at a high level during an erasing mode. The first and second current sources are respectively automatically controlled by a first and second auto-power control circuit to provide stable power outputs.

Find Patent Forward Citations

Fujiwara, Tetsuo. (1989). Beam controller for magneto-optical disc memory system (U.S. Patent No. 4843604). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/4843604

Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile

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