Equalizing and amplifying circuit in an optical signal receiving apparatus
CA 2021380 C · Owner: Ihara, Takeshi · Inventors: Ihara, Takeshi; Hamano, Hiroshi; Amemiya, Izumi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Disclosed is an equalizing and amplifying circuit in an optical signal receiving apparatus comprising a preamplifier circuit (102a) having an input terminal (406) connected to the output of a light receiving element (101), the preamplifier circuit amplifying the electrical signal from the light receiving element to output an amplified signal, and comprising an automatic gain control circuit (103) connected to the output of said preamplifier circuit. The preamplifier circuit (102a) comprises a transistor (402) having a common-base, a current source (403) connected to the emitter of the transistor, for supplying a bias current to the transistor, and a load resistor (404) connected to the …
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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 July 17, 1990 and granted May 10, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 17, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 17, 2012.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.