Photo signal amplification transmission system
CA 2235480 C · Owner: Nec Corporation · Inventors: Harano, Hiroshi; Maruyama, Naoki
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In a conventional photo signal amplification transmission system, since control is performed to make constant an output power, total output powers of all wavelengths are made constant when a multi-wavelength transmission is made. An output power of one wavelength is decreased and deviated from an optimum power. To solve the problem a transmission, photo amplifier 3, a relay photo amplifier 4 and a receiving photo amplifier 5 are provided with wavelength number information management sections 11, 12 and 13 respectively. An amplifying means is controlled in accordance with the number of wavelengths of the multi-wavelength signal which is obtained by the wavelength number information …
Read the whole patent
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, 1998 and granted March 26, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 21, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 21, 2020.
- 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.