Optical wavelength demultiplexer for a video passive optical network
CA 2196239 C · Owner: Swartz, Robert Gerald · Inventors: Ota, Yusuke; Swartz, Robert Gerald
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In a system where a second signal interferes with the detection of a first signal at an input, in which the second signal is composed of a low frequency component and a portion of the frequency spectrum that is higher than that of the first signal, then both signals are processed to eliminate such interferenceby filtering the second signal to eliminate the portion of the frequency spectrum that is higher than that of the first signal and eliminate the low frequency component of the second signal. Advantageously such processing is, done without affecting any low frequency component of the first signal.
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 January 29, 1997 and granted September 10, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 29, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 29, 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.