| 摘要 |
An electrostatic capacitive vibration sensor has a substrate, a through-hole, a vibrating electrode plate, and a fixed electrode plate opposite the vibrating electrode plate. The fixed electrode plate is subjected to vibration to perform membrane oscillation. Pluralities of acoustic holes are made in the fixed electrode plate. The vibrating and fixed electrode plate are disposed on a surface side of the substrate such that an opening on the surface side of the through-hole is covered. A lower surface of an outer peripheral portion of the vibrating electrode plate is partially fixed to the substrate. A vent hole that communicates a surface side and a rear surface side of the vibrating electrode plate is made between the surface of the substrate and the lower surface of the vibrating electrode plate. In addition, the acoustic hole has a smaller opening area except at the outer peripheral portion. |
