IP Library › Granted Patent US 4,701,640
Granted Patent Utility
US 4,701,640 · App. 06/710,225

Electret transducer and method of fabrication

Inventors: Dean W. Flygstad, Craig Tromborg
Patented Case View Patent ↗
Granted: Oct 20, 1987 Filed: Mar 11, 1985
Inventors
Dean W. Flygstad
Craig Tromborg
Assignee (at issue)
Telex Communications, Inc.

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Quick Facts
Patent No.
US 4,701,640
App. No.
06/710,225
Filed
1985-03-11
Granted
1987-10-20
Kind
A