Optical signal detection apparatus and method for preventing polarization signal fading in optical fiber interferometric sensor systems
CA 2121880 C · Owner: Arab-Sadeghabadi, Akbar · Inventors: Arab-Sadeghabadi, Akbar; Vonbieren, Karlheinz
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A photodetector includes a polarizer array and an array of photodetector elements. The polarizer array includes a plurality of polarizers having axes of polarization spaced apart by selected angles such that each optical signal incident on the polarizer array has a polarization component along at least one of the axes of polarization. The array of photodetector elements is arranged such that each of the photodetector elements receives light from a selected one of the polarizers. At least one of the photodetector elements receives parallel polarization components from the optical signals to form an electrical signal indicative of interference between the optical signals.
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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 April 21, 1994 and granted June 16, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 21, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 21, 2016.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.