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:
Sep. 17, 1991
Filed:
Jan. 30, 1990
Shigeru Takeda, Kumagaya, JP;
Satoshi Makio, Kumagaya, JP;
Hitachi Metals, Ltd., Tokyo, JP;
Abstract
A Faraday rotator device containing (a) a Faraday rotator, (b) a wire winding encircling the Faraday rotator for changing the magnetization state of the Faraday rotator, and (c) a hollow yoke surrounding the Faraday rotator and the wire winding for forming a substantially closed magnetic circuit together with the Faraday rotator, the hollow yoke having an opening in each of front and rear walls in alignment with the Faraday rotator for permitting a light to pass through the hollow yoke and the Faraday rotator. The optical switch containing a pair of polarizers disposed on front and rear sides of the Faraday rotator device, the magnetization direction of the Faraday rotator being reversible to change the optical path. The hollow yoke is made of a soft magnetic material or a semi-hard magnetic material.