Information recording medium and method and apparatus for recording and reproducing information using the same
CA 2235933 C · Owner: Suzuki, Motoyuki · Inventors: Tokushuku, Nobuhiro; Suzuki, Motoyuki; Fushimi, Tetsuya
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention provides an information recording and reproducing method of an information recording medium and an apparatus corresponding thereto. The information recording medium of the present invention includes radially wobbling groove portions having at least one of a substantially spiral-like track and concentric-shaped track. The information recording and reproducing method of this invention comprises the steps of generating a signal corresponding to the wobbling groove portions, and performing at least recording and reproducing information with use of an integer multiple clock of a frequency of the signal. Similarly the present, invention provides an apparatus for an …
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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 July 25, 1997 and granted April 10, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 25, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 25, 2019.
- 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.