Photographic processing apparatus
CA 2091576 A1 · Owner: Skye, David Albert · Inventors: Ward, Paul Courtenay; Earle, Anthony; Taylor, Nicholas John
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
It is known to use infrared densitometry to measure the variations in the optical density of photographic material. In photographic processing apparatus, it is important that the photographic material is transferred from one part of the apparatus to another at precisely the correct time to prevent damage to the material. Described herein is a method and apparatus for controlling the transfer or switching of photographic material from one processing tank to another of photographic processing apparatus during processing of the material. A threshold detector (30) is used to produce an output signal (40) indicative of a change in infrared density of the photographic material. The output signal …
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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
- Filed September 11, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended September 11, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 11, 2013.
- 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.