Optical isolator
CA 2069684 C · Owner: Arii, Mitsuzo · Inventors: Takeda, Norio; Shirai, Kazushi; Arii, Mitsuzo
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A high quality small-sized polarization independent optical isolator for use in an optical fiber communication system, wherein a pair of magneto-optical elements having Faraday rotation angle of 45 ~ 5 are contained in permanent magnets and arranged between a pair of birefringent crystal plates for splitting and combining an optical path of a laser light, and two polarizers arranged in parallel as being bounded on the midpoint of separated optical paths are interposed between the pair of magneto-optical elements, whereby a degree of worsening the optical isolation can be kept minimum against variations of an environmental temperature and wave length.
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed May 27, 1992 and granted November 11, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 27, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 27, 2014.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.