Optical disk, method for manufacturing the same, and method for recording and method for reproducing data using optical disk
CA 2472075 C · Owner: Ito, Motoshi · Inventors: Ito, Motoshi; Miyagawa, Naoyasu
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An optical disk includes a first information recording layer and second to N-th information recording layers (with N being an integer of two or greater) that are arranged further toward the side from which laser light is irradiated than the first information recording layer and which are arranged in order from the side near the first information recording layer. The first information recording layer includes a read-only control data region a first recording learning region for learning recording parameters to record data and a first user data recording region for recording user data. When taking at least one of the second to N-th information recording layers as an i-th information recording …
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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 June 23, 2004 and granted February 26, 2013. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 23, 2024.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 23, 2026.
- 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.