公开(公告)号：US4424419A

公开(公告)日：1984-01-03

申请号：US312375

申请日：1981-10-19

申请人： Guy J. Chaput ,  Edward M. Sich ,  Beverley W. T. Gumb

发明人： Guy J. Chaput ,  Edward M. Sich ,  Beverley W. T. Gumb

IPC分类号： H04R19/01 ,  H04R19/04

CPC分类号： H04R19/01

摘要： An electret microphone has a metal shield around it in order to guard against electromagnetic interference. Acoustic waves reach the electret element through a passage in the shield. The electret response is undesirably affected by an electric field produced by body capacitance when the microphone is brought close to a user's mouth. To overcome this effect, the microphone has a conductive film, transparent to acoustic waves, positioned between the passage and the electret element, the film contacting a grounded part of the casing. The conductive film can form an integral part of a microphone moisture barrier.

摘要翻译： 驻极体麦克风周围有一个金属屏蔽罩，以防止电磁干扰。 声波通过屏蔽中的通道到达驻极体元件。 当麦克风靠近用户的嘴时，驻极体响应受到体电容产生的电场的不利影响。 为了克服这种影响，麦克风具有位于通道和驻极体元件之间的对声波透明的导电膜，该膜接触壳体的接地部分。 导电膜可以形成麦克风防潮层的整体部分。