Multiple data surface optical data storage system
CA 2271541 C · Owner: Mitsubishi Denki Kabushiki Kaisha · Inventors: Rubin, Kurt Allan; Strand, Timothy Carl; Best, Margaret Evans
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An optical data storage system comprises a multiple data surface medium and optical head. The medium comprises a plurality of substrates separated by a light transmissive medium. Data, surfaces are located on the substrate surfaces which lie adjacent a light transmissive medium. The data surfaces are substantially light transmissive. The optical head includes an aberration, compensator to allow the head to focus onto the different data surfaces and a filter to screen out, unwanted reflected light.
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 April 15, 1992 and granted November 30, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 15, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 15, 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.