Optical recording medium
CA 1135413 A · Owner: Rca Corporation · Inventors: Spong, Fred W.; Levin, Leonard J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An optical recording medium comprises a plastic substrate coated with a first layer of a material which flows so as to fill in any surface imperfections or defects in the plastic substrate and hardens at low temperature to form a glossy, smooth, inert, hard and durable finish in, turn coated with a light reflecting layer and a light absorbing layer. The information is recorded with an intensity modulated focussed laser beam to melt or ablate the light absorbing layer and record information in the form of a reflective - antireflective pattern.
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
- Granted November 9, 1982. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended November 9, 1999.
- 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.