The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 29, 1977
Filed:
Aug. 22, 1972
Applicant:
Inventors:
Yoichi Kodera, Yokohama, JA;
Tetsuo Toyoda, Yokohama, JA;
Assignee:
Sony Corporation, Tokyo, JA;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01S / ; H04R / ;
U.S. Cl.
CPC ...
29592 ; 29594 ; 307 / ; 1791 / ; 1791 / ; 156322 ; 156285 ; 156252 ;
Abstract
An improved method for making a backplate assembly for an electret transducer used in a microphone wherein a synthetic resin film such as polytetrafluoroethylene or fluorinated ethylene-propylene copolymer is attached to a plate member having a flat conductive surface and which has been heated so as to securely attach the film thereon and charging said synthetic film to form an electret.