Patent ID: 9668061
Date: 2017-05-30
CPC Classifications: H04R,Y10T

Claim:
1. An electrodynamic acoustic transducer comprising: a diaphragm; and a fixed pole which is arranged with a predetermined interval from the diaphragm and faces the diaphragm, and which has an electret dielectric film on a surface facing the diaphragm, the electret dielectric film being divided into a plurality of segment regions, and each of the plurality of segment regions having a predetermined surface potential given by a polarization processing, wherein the fixed pole further includes non-polarized regions for separating the segment regions so that the segment regions are separated from each other, wherein the plurality of segment regions includes a center region and circumference regions radially arranged around the center region, which are separated by the non-polarized regions, and wherein the electret dielectric film is a flat film separated into the segment regions, wherein the segment regions are negatively charged, and wherein the non-polarized regions separate the segment regions.