Electret loudspeaker device
US8855339B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 16, 2012 |
| Grant date | Oct 7, 2014 |
| Priority date | — |
| Expiry date | Aug 16, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R7/10
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An electret loudspeaker device including a diaphragm, a first perforated electrode and a first spacer is provided. The diaphragm includes a first electret, a second electret, a polymer layer and an electrode layer. At least one layer of the first electret or the second electret is formed by expanded polytetrafluoroethylene. The second electret is stacked on one side of the first electret, while the electrode layer is stacked on the opposite side of the first electret. The polymer layer is made of a hydrophobic material and is disposed on the second electret. The first perforated electrode is stacked on a first spacer and close to the polymer layer. The first spacer disposed between the diaphragm and the first perforated electrode supports the first perforated electrode over the diaphragm and defines a first chamber. A fabrication method of the electret loudspeaker device is also provided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.