Surface elastic wave filter
CA 2015227 C · Owner: Takeuchi, Yoshihiko · Inventors: Takeuchi, Yoshihiko; Yatsuda, Hiromi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A surface elastic wave filter includes a plurality of input interdigital transducers for receiving a highfrequency input signal, and a plurality of output interdigital transducers for producing an output signal derived from the input signal and having predetermined frequency characteristics. Each of the input and output interdigital transducers having a pair of confronting connectors for receiving the input signal and extracting the output signal respectively, and a pair of groups of interdigitating electrode fingers extending from the connectors. The input and/or output interdigital transducers include fingerwithdrawn interdigital transducers with electrode fingers selectively withdrawn in …
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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 April 24, 1990 and granted January 25, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 24, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 24, 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.
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.