Preamplifier for optical communication
CA 2198161 A1 · Owner: Sumitomo Electric Industries, Ltd. · Inventors: Nishiyama, Naoki
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The photocurrent generated by a photodiode receiving light substantially flows through a feedback resistor when the incident light intensity is low. As the incident light intensity increases the source and, drain of a FET connected in parallel to the feedback resistor establish a conducting state therebetween whereby the photocurrent is divided into a current flowing through the feedback resistor and a current flowing through the FET connected in parallel to the feedback resistor. Accordingly, transimpedance is equivalently lowered, while the feedback resistor is restrained from lowering the output potential. When the incident light intensity is further increased a, gate bias current flows …
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 February 21, 1997. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended February 21, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 21, 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.