Patent ID: 7050597
Filing Date: 2006-05-23
Classification: H04R

Abstract:
1. A directional capacitor microphone including a microphone case having a front and a rear acoustic terminals and a vibration plate disposed at the side of the front acoustic terminal in the microphone case with the vibration plate strained on a support ring, the directional capacitor microphone further including a fixed electrode disposed at the side of the rear acoustic terminal in the microphone case and supported by a support with the fixed electrode facing to the vibration plate, the directional capacitor microphone further including an acoustic resistor mounted in an acoustic path from the rear acoustic terminal to the back surface of the vibration plate and a lead for connecting the fixed electrode to an impedance converter, the directional capacitor microphone comprising: a large diameter-column being able to support the fringe of the fixed electrode; a small diameter-column having a smaller diameter than that of the large diameter-column and communicating to the rear end of the large diameter-column with the both columns concentrically disposed, said small diameter-column including, an acoustic path formed with the small and the large diameter-columns; an acoustic resistor housed in the large diameter-column; and wherein the support is an electrically conductive column.