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. 13, 1990
Filed:
Dec. 29, 1987
Applicant:
Inventor:
Keiji Nakatsu, Amagasaki, JP;
Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
369 32 ; 369 43 ; 369 46 ;
Abstract
An optical disk reading apparatus having a carriage on which a tracking actuator and a photosensor unit are mounted and driven by a head actuator for moving a spot of a light beam in a direction traversing tracks on an optical disk and for detecting first position and second position signals indicative of the position of the spot on the tracks through addition and subtraction of the electric signals corresponding to changes in the quantities of light reflected from the tracks upon the movement of the spot and including circuitry for accurately placing the spot on a desired track of the disk even when the first and second position signals contained omissions.