Electret loudspeaker device
US8699730B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 16, 2012 |
| Grant date | Apr 15, 2014 |
| Priority date | — |
| Expiry date | Aug 16, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R19/013
- 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 has an electret layer and an electrode layer. The first perforated electrode is stacked on a side of the diaphragm near the electret layer, and has multiple holes. The first spacer is stacked between the diaphragm and the first perforated electrode, and includes a first distribution area and plural second distribution areas. The first distribution area has first openings penetrating through the first spacer, and each first opening has a first opening space volume between the diaphragm and the first perforated electrode. Each second distribution area has second openings penetrating through the first spacer, and each second opening has a second opening space volume between the diaphragm and the first perforated electrode. A difference between the first and the second opening space volumes is greater than 10%.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.