Optical recording medium and disc cartridge
CA 2310706 A1 · Owner: Watanabe, Tetsu · Inventors: Kaeriyama, Takuya; Fujiie, Kazuhiko; Maeda, Yasuaki
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An optical recording medium is provided which has a substrate and a signal recording layer provided on the substrate and in which an information signal is, recorded in the form of microscopic pits. A light beam is focused on the signal, recording layer and some change of the light beam carried by a return light from the, signal recording layer is detected to read the information signal recorded on the signal, recording layer. The optical recording medium has a diameter of 65 mm or less and, a thickness of 0.4 to 0.7 mm. An information signal recording area extends outwardly from a radial position of 12.5 mm or less from the center of the medium. The ratio in area between the …
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 June 6, 2000. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended June 6, 2020.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 6, 2022.
- 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.