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:
Jun. 06, 1995
Filed:
Sep. 09, 1993
Masahiro Birukawa, Hirakata, JP;
Norio Miyatake, Kobe, JP;
Yuuichi Fukamachi, Ikoma, JP;
Yoshihiko Kudoh, Yawata, JP;
Yasumori Hino, Hirakata, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
The present invention relates to a magneto-optical recording medium, in which are provided at least a reading layer and a writing layer on a substrate. A track guide groove is formed in the medium so as to include in-groove portions and on-land portions. Pits are formed on a portion along the track longitudinally adjacent where an in-groove portion and where no guide groove exists. Pits are also formed in an on-land portion between the in-groove portions of the track guide groove. Only a portion where a temperature has been raised by optical beam irradiation is read, while a domain of a writing layer is copied on the writing layer, whereby a writing/reading operation can be effected with narrower track pitches.