Patent ID: 7082810

Claim:
A gas sensor including a detection element provided facing a predetermined flow path of a gas and receiving a predetermined signal causing the detection element to vibrate, and detecting means for transmitting a vibration wave having energy generated by vibration of the detection element in the flow path direction to detect characteristics of the gas, the gas sensor comprising: a housing for housing the detection element in a form capable of transmitting the vibration wave for detection in the flow path direction; an attenuation member, provided in the housing, for attenuating the energy of a vibration wave emitted in a direction different from the transmitting direction and colliding with the attenuation member; and a filled layer formed by introducing a filler into the housing, said filled layer embedding at least the detection element, wherein the attenuation member is a surface member provided on the surface of the detection element opposite the surface of the filled layer, said surface member comprising a porous body, at least a part of the porous body is embedded in the filled layer, and the filler penetrates or permeates into the porous body.