Optical receiver board, optical wavelength-tuning filter module used foroptical receiver board, and actuator for optical wavelength-tuning filter module
CA 2206945 A1 · Owner: Sumitomo Osaka Cement Co. Ltd. · Inventors: Ogata, Takaaki; Nakamura, Takashi; Koga, Tadashi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An optical receiver board is disclosed. In the optical receiver board, a signal light is amplified in an optical fiber amplifier. The amplified signal light is supplied to an electrically driven optical wavelength-tuning filter such as a multi-layered film interference filter through which a signal, light of a predetermined wavelength bandwidth is transmitted. The transmitted signal light is divided into first and second signal lights. The first signal light is converted to an electric signal which is amplified by an equalizing amplifier and an amplified electric signal is supplied to a discrimination circuit, in which an information electric signal is generated by using a timing signal. …
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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 June 2, 1997. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended June 2, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 2, 2019.
- 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.