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SE7410408L
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PROCEDURE FOR MANUFACTURING AN ELECTRIC MICROPHONE WITH A CAREFULLY DETERMINED AIR GAP.
Assignee: Ericsson Telefon Ab L M
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Filing: 1974-08-15
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Granted: —
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Expires: 1994-08-15
Abstract
Abstract 1510833 Electret microphones TELEFONAKTIEBOLAGET L M ERICSSON 12 Aug 1975 [15 Aug 1974] 33607/75 Heading H4J [Also in Division H1] In an electret microphone wherein the movable electrode comprises PTFE electret layer 3 and polyester layer 2 bearing metallized layer 4, air gaps are provided between electret layer 3, fixed plate 1 and layer 2 by hot embossing a mesh pattern on each side of the electret layer before completion of polarization using a glass web.
Inventors
- 👤 N A M Andersson
- 👤 R B G Jonsson
Bibliographic Details
Application Number
—
Jurisdiction
SE
Data Source
google_patents
Last Synchronized
2026-11-03 05:38
CPC Classifications
H; H04; H04R; H04R19/00; H04R19/01; H04R19/016
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