Information recording and retrieval system
CA 2007262 C · Owner: Sharp Kabushiki Kaisha · Inventors: Terashima, Shigeo; Maeda, Shigemi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An information recording and retrieval system used for recording and playing back programs on and from a rewritable recording medium which includes absolute addresses; an information recording area for storing programs input from outside the system; and a TOC area for storing supplemental data on the programs recorded in the information recording area. This system comprises: (1) a magnetic coil and an optical head which function in combination (a) to successively record the items of supplemental data in the TOC area in such a way that each item of supplemental data is repeatedly recorded a plurality of times, each item of supplemental data at least comprising an identification number …
Read the whole patent
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 January 5, 1990 and granted July 20, 1993. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 5, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 5, 2012.
- 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.