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. 01, 1988
Filed:
Oct. 17, 1985
Masataka Itoh, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
In a magneto-optical reproducing head including first and second beam splitters (21, 22) and a Faraday effect member (25) between the splitters to suppress return to a laser beam source (11) of a reversed laser beam reversedly sent from a magneto-optical recording medium (12) on which a forward laser beam is incident, the second beam splitter is made to have a transmissivity of at least 0.5 for a p-polarized component. For an s-polarized component, the second beam splitter has a reflectivity which is substantially equal to unity as usual. In order to produce a servo control signal, a signal producing circuit (17) is made to receive an s-polarized component which is substantially totally reflected in the first beam splitter and into which the Faraday effect member converts the p-polarized component having reversedly passed through the second beam splitter. The transmissivity of the second beam splitter should preferably be at least 0.75 and not greater than 0.8. An optically active member (35) is preferably interposed between the Faraday effect member and either the first or the second beam splitter. The head is readily used in recording information on the recording medium and/or in erasing such information.