| 摘要 |
It is a primary object of the present invention to suppress the variability of an acoustic resistance of sound passing from a rear acoustic terminal to the back surface of a vibration plate by sufficiently obtaining the contact area between an acoustic resistor and its storage portion even in a capacitor microphone having a small diameter. In order to achieve the object, as shown in FIG. 3, a support 140 of a fixed electrode 130 is formed as an electrically conductive column including a large and a small diameter-columns with the both columns disposed concentrically. The difference between each of the inner diameters of the large and the small diameter-columns is increased as possible as it can so that the contact area between the acoustic resistor 151 housed in the large diameter-column 141 and the bottom 141a of the large diameter-column can be increased. Therefore, the variability of the acoustic resistance can be suppressed.
|
