Optical disk and optical information recording method
CA 2036853 C · Owner: Ohno, Eiji · Inventors: Yamada, Noboru; Ohno, Eiji; Akahira, Nobuo
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention relates to a rewritable phase change optical disk and a method of recording optical information on the optical disk. On the optical disk a first dielectric film, a recording film, a second dielectric film and a reflecting film are stacked on a substrate in that order. The recording film has a composition defined by a formula GexSbyTez wherein x, y and z are atomic percentages ranging from 7 to 17, 34 to 44 and 44 to 54 respectively, the, x, y and z totalling 100. The recording film has a thickness of 10 to 35 nm. The second dielectric film has a thickness of 5 to 40 nm. The reflecting film is made of one or an alloy of at least Au, Al, Ti, Cr and Ni and has a thickness …
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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 February 21, 1991 and granted October 22, 1996. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 21, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 21, 2013.
- 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.