Wireless headphone
CA 2012487 C · Owner: Sony Corporation · Inventors: Abe, Kensaku
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In a wireless headphone in which an infra-red signal light transmitted from a transmitting apparatus is received and a received output is reproduced as an audible sound by a headphone unit portion, a first light receiving element is provided on a top portion of a head band portion so that when a listener wears the wireless headphone on the head a, light receiving surface of the first light receiving element is directed rearward and second and third light receiving elements are provided on the pair of headphone unit portions so that, when the listener wears this wireless headphone on the head, light receiving surfaces of the second and third light receiving elements are directed forward …
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 March 19, 1990 and granted October 3, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 19, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 19, 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.