Optical record cards
CA 1312951 C · Owner: Polaroid Corporation · Inventors: Slafer, Warren D.; Kime, Milford B.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An optical information storage card having a rectangular format and comprising (a) a surface having on at least one side, thereof, surface relief formations forming an optically machine readable information surface; and (b) a protection layer being in overlying juxtaposed relationship to the information surface. The substrate and the protection layer are transmissive to a selected range of electromagnetic radiation usable for optically reading the information surface. The information surface has a generally spiral or concentric format whereby the information surface can be read as the card is rotated round at least one axis.
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 January 19, 1993. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended January 19, 2010.
- 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.