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:
Oct. 07, 2014
Filed:
Aug. 16, 2012
Chih-kung Lee, Taipei, TW;
Yu-chi Chen, Taipei, TW;
Han-lung Chen, Taipei, TW;
Hsu-ching Liao, Taipei, TW;
Wen-hsin Hsiao, Taipei, TW;
Chih-Kung Lee, Taipei, TW;
Yu-Chi Chen, Taipei, TW;
Han-Lung Chen, Taipei, TW;
Hsu-Ching Liao, Taipei, TW;
Wen-Hsin Hsiao, Taipei, TW;
National Taiwan University, Taipei, TW;
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.