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:
Feb. 16, 1993
Filed:
Aug. 28, 1989
Applicant:
Inventors:
Hidehiro Ishii, Saitama, JP;
Hiroshi Takeya, Saitama, JP;
Chiharu Miura, Saitama, JP;
Tatsuya Fukuda, Saitama, JP;
Assignee:
Pioneer Electronic Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
369 4429 ; 369 4434 ; 369 4435 ; 369 58 ;
Abstract
A method for setting the loop gain in a focusing servo loop of a disc player. The loop is opened and the objective lens is moved repeatedly up and down about the focusing point while the disc is slowly rotated, thereby generating an S-shaped focusing error curve. The S-shaped error curve is sampled and a loop gain is determined based on the sampled values. If an eject instruction occurs during the loop gain setting process, a braking pulse is applied to a spindle motor for stopping the disc rotation.