Patent attributes
An ultrasonic sensor includes an ultrasonic detecting element, an acoustic matching member, and an oscillation damping member. The ultrasonic detecting element detects an ultrasonic wave. The acoustic matching member has a receiving surface that is adapted on a side of the certain object to be exposed to a space, in which the detected body exists. The receiving surface receives the ultrasonic wave reflected by the detected body. The acoustic matching member is made of a material having an acoustic impedance larger than that of air and smaller than that of the ultrasonic detecting element. The oscillation damping member is disposed between an attachment portion and the acoustic matching member. The attachment portion is adapted for attaching the ultrasonic sensor to the certain object. The oscillation damping member damps transmission of oscillation from the certain object to the acoustic matching member.
