Patent ID: 7590252

Claim:
An electret condenser microphone comprising: a vibrating diaphragm in which one face is electrically conductive; a fixed electrode which is placed to be opposed to said vibrating diaphragm via an air layer; a dielectric layer which becomes an electret for storing charges in one of said vibrating diaphragm and said fixed electrode; circuit means for converting an electrostatic capacity between said vibrating diaphragm and said fixed electrode to an electric signal; external connecting means for leading out the electric signal; and a first spacer which forms and holds a predetermined positional relationship between said vibrating diaphragm and said fixed electrode, said microphone being incorporated in a metallic case while exposing said external connecting means, wherein an outer face of said case is coated by a nonmetallic material in which a deforming temperature is higher than a charge dissipating temperature of said dielectric layer that becomes said electret.