Magneto-optical recording method and magneto-optical memory device
CA 2080981 C · Owner: Katayama, Hiroyuki · Inventors: Hirokane, Junji; Mieda, Michinobu; Ohta, Kenji
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A magneto-optical recording method for rewriting of information includes the initial step of projecting a light beam whose intensity varies in response, to information to be recorded onto a magnetic thin film with perpendicular magnetization while an external magnetic field of a constant intensity is applied thereto. The magnetization direction of an irradiated area of the magnetic thin film with perpendicular magnetization is arranged in the direction of the external magnetic field when a light beam at high intensity is projected while it is arranged, in the direction of a demagnetizing field opposite to the direction of the external magnetic field generated by magnetization in the …
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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 October 20, 1992 and granted February 16, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 20, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 20, 2014.
- 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.