Recording and/or reproduction apparatus of an optical disc
CA 2005341 C · Owner: Sony Corporation · Inventors: Eguchi, Naoya; Saitou, Kimihiro; Wachi, Shigeaki
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A recording and/or reproduction apparatus of an optical disc having recording tracks in which mirror areas are formed incorporates an optical head for recording or reproducing information signal onto or from the optical disc which has an optical detector for detecting a tracking error signal by a push-pull method; a fine actuator for precisely actuating the optical head finely; detecting means for detecting an output signal of the optical detector responding to reflected light from the mirror area; and driving means for driving the fine actuator in response to an output signal of the detecting means during the seeking operation.
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 December 13, 1989 and granted February 8, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 13, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 13, 2011.
- 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.