Granted Patent
Utility
US 4,575,406 · App. 06/633,290
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Inventor:
Warren D. Slafer
Patented Case
View Patent ↗
Granted: Mar 11, 1986
Filed: Jul 23, 1984
Inventor
Warren D. Slafer
Assignee (at issue)
Polaroid Corporation
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.