Optical fiber amplifier having light surge preventing function
CA 2176310 C · Owner: Nec Corporation · Inventors: Shibuya, Takashi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
At a post stage of an amplifying optical fiber such a, means is provided that detects a level of light having a center wavelength of the amplified signal light and also a, level of light having a wavelength different from that of this center wavelength, and further another means is provided which compares the level of the light having these wavelengths and, controls an output of a pumping light source based on this comparison result. To detect the intensity of the light having these two wavelengths, two light branching devices and, light receiving devices are arranged via the respective light band-pass filters for passing therethrough the light having the above-described wavelengths at the …
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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 10, 1996 and granted April 18, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 10, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 10, 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.