Recorded image detection system for updatable microfilm
CA 1161896 A · Owner: Bell & Howell Company · Inventors: Hertel, Heinz E.; Flint, John R.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention is used in photo-recording machines such as microfiche recorders, which receive a document and record an image of the document of a photo-recording medium such as photoplastic film. The invention inhibits double exposures on frames of the film by use of distinctive indicator marks recorded on the film at preselected locations called indicator mark fields. The presence or absence of an indicator mark in such an indicator mark field signifies respectively, that its corresponding frame is or is not available for recording a document image. In an improved recorder prior, to a proposed recording, a detector scans the indicator mark field corresponding to the frame selected …
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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 February 7, 1984. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 7, 2001.
- 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.