Apparatus for discriminating an optical signal from others and an apparatus for tuning an optical wavelength filter used in the same
CA 1279414 C · Owner: Nec Corporation · Inventors: Nishio, Makoto
Overview
Its claims, description and drawings are in the Canadian Patents Database.
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An apparatus for discriminating an optical signal from others comprises a circuit for adding one of discriminating signals to a corresponding optical signal. The discriminating signal is of a frequency lower than a band of the optical signal. Therefore the, discriminating signal is easily detected by being passed through, for instance, a low-pass filter. An apparatus for tuning an optical wavelength filter used in apparatus for discriminating an optical signal from others comprises a circuit for frequencymodulating an optical signal by a first discriminating signal and for amplitude-modulating the optical signal by a second discriminating signal having a phase information of the first …
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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
- Granted January 22, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended January 22, 2008.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.