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:
Aug. 17, 1993
Filed:
Aug. 09, 1991
Takashi Ogawa, Yokohama, JP;
Tetsuo Kanno, Ebina, JP;
Yoshiaki Aota, Oyaguchi-Kita, JP;
Yuji Kitamura, Yokohama, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
An apparatus for measuring an optical output of an optical pickup device disposed in an optical disk drive unit has a dummy cartridge approximately of the same type as a disk cartridge mounted to the optical disk drive unit; a light-receiving element disposed in a predetermined position of the dummy cartridge; an optical level measuring display device for inputting the light-receiving signal thereto and displaying a measured value of the optical output; and a controller for controlling an operation of the optical disk drive unit such that this optical disk drive unit performs a predetermined operation for measuring the optical output. The above measuring apparatus may further comprise a connector device for externally outputting the light-receiving signal of the light-receiving element. In this case, the optical level measuring display device inputs the light-receiving signal thereto through the connector device. An apparatus for measuring a magnetic field distribution of a magnetic head disposed in a magnetooptic disk drive unit and generating an auxiliary magnetic field is also shown.