Optical fiber filter
CA 2188335 C · Owner: Okude, Satoshi · Inventors: Okude, Satoshi; Wada, Akira; Sakai, Tetsuya
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention relates to an optical fiber filter provided with a portion which selectively reflects or transmits light of a specific wavelength this portion comprised of a multimode optical fiber in which the refractive index of the core changes periodically along the longitudinal direction thereof. Furthermore this multimode optical fiber has an input end and an output end with at least the input end of the multimode optical fiber being connected to a single mode optical fiber. As a result of forming an optical fiber filter in this way it is possible to realize an optical fiber filter that exhibits no transmission loss at wavelengths other than the center wavelength.
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 October 21, 1996 and granted May 1, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 21, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 21, 2018.
- 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.