Method for wavelength-dependent compensation in a variable optical attenuator
CA 2233175 C · Owner: Ando Electric Co. Ltd. · Inventors: Matsumoto, Yoshinori; Sugimura, Hiroyuki
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention provides a wavelength dependent compensation method in a variable optical attenuator which cam precisely set the amount of attenuation within, a wide range of wavelengths and to provide superior operability. An optical signal, 20a is emitted from a white light source 20 incident on a monochromator 21 and under, control of a CPU 24, only an optical signal 20b of a specific wavelength is extracted and, is made incident on a variable optical attenuator 22; in optical attenuator 22 under, control of a CPU 24, optical signal 20b is attenuated; the power of attenuated optical, signal 20c is measured by power measurer 23 under control of a CPU 24 producing, compensating …
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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 July 29, 1997 and granted August 20, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 29, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 29, 2019.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.