Patent ID: 8627725

Claim:
A capacitance type vibration sensor comprising: a substrate including a hollow portion; a vibration electrode plate, which is arranged facing the hollow portion at an upper surface side of the substrate and which vibrates by sound pressure, wherein the vibration electrode plate comprises a first fixed part provided at a first corner of the vibration electrode plate and a second fixed part provided at a second corner of the vibration electrode plate; and a fixed electrode plate which is arranged facing the vibration electrode plate and which is opened with a plurality of acoustic perforations passing therethrough in a thickness direction; the capacitance type vibration sensor comprising: an air path, which communicates a space between the vibration electrode plate and the fixed electrode plate to the hollow portion, between an upper surface of the substrate and a lower surface of the vibration electrode plate in at least one part of a periphery of the hollow portion, and between the first fixed part and the second fixed part, wherein an air escape portion for escaping the air in the air path in the thickness direction of the vibration electrode plate is formed at a site of the vibration electrode plate or the substrate facing the air path.