Hearing aids
CA 1202111 A · Owner: Reynolds & Lawrence Industries Limited · Inventors: Laurence, Roger F.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
IMPROVEMENTS IN OR RELATING TO HEARING AIDS" A hearing aid comprising a microphone whose output signal is split by high and low pass filters and supplied to two channels. Each channel includes a variable gain circuit . The outputs of the variable gain circuits are mixed by a mixer and supplied to an earphone . The turnover frequencies of the filters are such that one channel limits the dynamic range of vowels whereas the other channel limits the dynamic range of consonents, thus preventing interaction and masking of consonents by preceding vowels. The intelligibilty of speech is thus improved.
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
- Granted March 18, 1986. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended March 18, 2003.
- 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.