Electret condenser microphone unit
US5272758A · kind A · utility
25Cited by
3References
19Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 16, 1992 |
| Grant date | Dec 21, 1993 |
| Priority date | — |
| Expiry date | Apr 16, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R19/016
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An electret film is formed on the rear side of a front face plate of a cylindrical capsule made of aluminum . Closely in spaced opposition thereto, an electrically conductive diaphragm is held by an electrically conductive holding member. A wiring board provided behind the holding member closes the rear end of the capsule. The rear end of the capsule is bent on the rear periphery of the wiring board, and calked thereat. In the capsule, an impedance conversion IC device is connected to the electrically conductive holding member and the wiring board.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.