Self-developing motion picture viewer having controlled film imbibition
CA 1098356 A · Owner: Polaroid Corporation · Inventors: Holmes, William A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A programmable viewing system for processing and viewing cassette contained photographic film strips in which, the film is driven through forward and rewind advancement for film development operations and then automatically projected and again rewound, includes an electronic switching arrangement for de-energizing the system drive motor at the termination of the development rewind to prevent cinching or stressing of the film strip on the spool while developing fluid reacts with the exposed emulsion. Then the motor is automatically turned on again after completion of the fluid reaction period.
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 March 31, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended March 31, 1998.
- 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.