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:
Mar. 17, 1998
Filed:
Jan. 19, 1995
Applicant:
Inventors:
Assignee:
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Primary Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
369 4414 ; 369 4423 ; 369 4427 ; 369 58 ;
Abstract
An optical head apparatus includes a stationary optical system having a light source and a detector for detecting light reflected by a recording medium, which stationary optical system is arranged at a position fixed to the recording medium. Plural objective lenses for focusing/irradiating light emitted from the light source onto the recording medium are arranged on a rotating blade which is provided to be rotatable in a direction parallel to the recording medium. By controlling the waveform of a current to be supplied to a tracking coil, the blade is rotated and a desired one of the objective lenses is located on an optical axis of the light irradiated onto the recording medium.