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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 4972400 B1

PDFFull Text
Date of Patent:
Nov. 20, 1990

Filed:

Mar. 28, 1988

Optical pickup apparatus having switch for allowing positional adjustment

Applicant:
Inventors:

Toru Kuwabara, Gunma, JP;

Kazuo Hirasawa, Kyoto, JP;

Kiyomitsu Nishimura, Hyogo, JP;

Assignee:

Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;

Attorney:

Wolf, Greenfield & Sacks

Primary Examiner:

Aristotelis M Psitos

Assistant Examiner:

W R Young

Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
369 4429 ; 369 4435 ; 369120 ; 369124 ;
Abstract

The invention comprises an optical pickup apparatus including a photodetector which detects a laser beam reflected from information tracks of a disk and an amplifier circuit which amplifies the outputs of the photodetector. The photodetector and the amplifier circuit are integrally combined. A preamplifier circuit is also provided for positional adjustments. A switch is included within the amplifier for alternately inhibiting the path of the outputs of the photodetector to the amplifier circuit to allow for positional adjustment with the preamplifier and enabling the path of the outputs of the photodetector to the amplifier circuit for normal operation.

Find Patent Forward Citations

Kuwabara, Toru. (1990). Optical pickup apparatus having switch for allowing positional adjustment (U.S. Patent No. 4972400). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/4972400

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

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