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:
Dec. 08, 1992
Filed:
Nov. 07, 1990
Applicant:
Inventors:
Kouichi Yamada, Amagasaki, JP;
Isao Watanabe, Amagasaki, JP;
Assignee:
Mitsubishi Denki Kabushiki Kaisha, Hyogo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B / ; G11B / ; G11B / ;
U.S. Cl.
CPC ...
369 13 ;
Abstract
A magneto-optical recording apparatus records an information signal on a disk by illuminating a magnetic layer on the disk with a pulsed laser beam having a frequency at least twice the maximum frequency of the information signal, and applying a magnetic field with a polarity switched according to the information signal to the spot illuminated by the laser beam. To ensure erasure of old information, the apparatus can modify the peak power level, bottom power level, duty cycle, or frequency of the pulsed laser beam according to the radial position of the beam on the disk.