IP Library › Granted Patent US 4,978,991
Granted Patent Utility
US 4,978,991 · App. 07/459,126

Open-loop stepper motor controlled shutter

Inventor: David L. Farrington
Patented Case View Patent ↗
Granted: Dec 18, 1990 Filed: Dec 29, 1989
Inventor
David L. Farrington
Assignee (at issue)
Polaroid Corporation

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Quick Facts
Patent No.
US 4,978,991
App. No.
07/459,126
Filed
1989-12-29
Granted
1990-12-18
Kind
A