| 摘要 |
<p>The variation of the amount of charge given to an electretized dielectric film because of ionizer irradiation is reduced, and the variation of the sensitivity of a microphone is also reduced. A conductor (4) is maintained in a floating state without grounding the conductor (4). In consequence, current pass to an ionizer (1) is prevented, and draw-in of ions emitted from the ionizer into the dielectric film (32) due to the electric field produced by a loop circuit formed is reduced. Therefore, an effect in reducing the variation of the amount of charge given by the ionizer (1) is produced, an uneven amount of charge is reduced, leading to reduction of the variation of the microphone sensitivity.</p> |
