IP Library › Granted Patent US 4,621,898
Granted Patent Utility
US 4,621,898 · App. 06/476,297

Directional optical filter

Inventor: Richard L. Cohen
Patented Case View Patent ↗
Granted: Nov 11, 1986 Filed: Mar 17, 1983
Inventor
Richard L. Cohen
Assignee (at issue)
ALLIED CONSULTING, INC.

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Quick Facts
Patent No.
US 4,621,898
App. No.
06/476,297
Filed
1983-03-17
Granted
1986-11-11
Kind
A