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:
May. 04, 1993
Filed:
Apr. 11, 1991
Tami Isobe, Yokohama, JP;
Shigeyoshi Misawa, Tokyo, JP;
Kiyoshi Yokomori, Yokohama, JP;
Syunsuke Fujita, Yokohama, JP;
Magane Aoki, Yokohama, JP;
Yoshinobu Nakayama, Kawasaki, JP;
Hiroyoshi Funato, Chigasaki, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A magneto-optical signal detection device comprising a thin film type optical waveguide unit having a substrate on which a waveguide is formed. The unit has a coupling portion for coupling two polarization components simultaneously in a same plane of the waveguide as a TE mode and a TM mode. The modes TE and TM are included in reflection light reflected from a magneto-optical recording medium and perpendicular to each other. The unit also has a TE-TM mode separating portion having a taper boundary. A waveguide layer is gradually thinned in the taper boundary toward an outer end thereof.