VARIABLE DIRECTIONAL ELECTRET CONDENSER MICROPHONE UNIT, AND CONDENSER MICROPHONE

摘要

PROBLEM TO BE SOLVED: To provide a variable directional electret condenser microphone unit which is variable in directivity continuously from nondirectivity to bidirectivity, and to provide a microphone using the unit.;SOLUTION: The variable directional electret condenser microphone unit has a bidirectional condenser microphone unit constituted by opposing fixed electrodes of unidirectional electret condenser microphone units, each having a diaphragm, a diaphragm holder with the diaphragm fixed thereto, and a fixed electrode disposed opposite the diaphragm across a gap to form a capacitor with the diaphragm, arranging an acoustic resistance material fixed between the fixed electrodes with an insulating seat, and coupling them integrally; and a variable capacitance capacitor connecting the fixed electrode of one unidirectional electret condenser microphone unit to the diaphragm of another unidirectional electret condenser microphone unit.;COPYRIGHT: (C)2008,JPO&INPIT