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:
Oct. 24, 1995
Filed:
Dec. 27, 1993
Hajime Machida, Tokyo, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A method of magneto-optical recording and overwriting information onto a double-layer magneto-optical recording medium which has laminated first and second magnetic layers having different coercive forces at a lower operation temperature and a higher operation temperature of which one is a recording operation temperature and the other is an erasing operation temperature, without using an initializing external magnetic field. The method includes the steps of recording by applying a laser beam to an area of the recording medium at a power level corresponding to one of these operating temperatures and erasing by applying a laser beam to an area of the recording medium at a different power level corresponding to the other of the operating temperatures, while applying a bias magnetic field to the magneto-optical recording medium with the same magnetization direction during both recording and erasing, the intensity of the bias magnetic field being greater than the coercive forces of the first and second magnetic layers at the lower operation temperature.