IP Library › Granted Patent US 4,891,843
Granted Patent Utility
US 4,891,843 · App. 06/469,489

Electret microphone

Inventors: Frank S. Paulus, Jr., Isaac Tuah-Poku
Patented Case View Patent ↗
Granted: Jan 2, 1990 Filed: Feb 24, 1983
Inventors
Frank S. Paulus, Jr.
Isaac Tuah-Poku
Assignee (at issue)
AT&T Technologies Incorporated

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Quick Facts
Patent No.
US 4,891,843
App. No.
06/469,489
Filed
1983-02-24
Granted
1990-01-02
Kind
A