Optical disc and optical disc address reading apparatus and method
CA 2396780 C · Owner: Matsushita Electric Industrial Co. Ltd. · Inventors: Kobayashi, Yoshiharu; Furumiya, Shigeru; Ishida, Takashi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An optical disc having marks for dispersed addresses that can be easily detected with high precision. A dispersed address comprises synchronization marks, positive marks, and negative marks. Synchronization marks, positive marks, and negative marks are formed along a groove as partial discontinuities or partial modifications in the wobbled groove.
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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 December 27, 2000 and granted March 13, 2012. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 27, 2020.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 27, 2022.
- 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
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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.