Scanning shutter blade arrangement with ambient and flash ranges
CA 1105757 A · Owner: Polaroid Corporation · Inventors: Johnson, Bruce K.; Whiteside, George D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An exposure control for a camera of the type having scanning type shutter blade elements driven by a walking beam to provide a progressive variation in effective exposure and light sensing apertures. A control is provided so that in an artificial scene lighted mode during an exposure cycle, the scanning blades cause the effective exposure aperture to progressively increase toward the full open f/stop for the camera. In addition the scanning blades cause the effective photocell aperture to increase at a relatively low rate until a time when the effective exposure aperture equals a predetermined f/stop somewhat below the full open f/stop. The source of artificial illumination is then fired …
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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 July 28, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended July 28, 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.