Patent ID: 7714482

Claim:
An ultrasonic sensor comprising: a plurality of sensor elements arranged in an array, each sensor element including: an ultrasonic sensing element for sensing an ultrasonic wave reflected by an object; and an acoustic matching member having a reception surface for receiving the ultrasonic wave reflected by the object, wherein the reception surface is directed to a space where the object is expected to exist, wherein a surface of the acoustic matching member opposed to the reception surface is connected with the ultrasonic sensing element, wherein the acoustic matching member conducts the ultrasonic wave received by the reception surface to the ultrasonic sensing element; and a bonding member having a thickness approximately equal to a space interval between adjacent ultrasonic sensing elements, wherein the bonding member adhesively fixes the plurality of sensor elements, wherein the bonding member includes a portion contacting each ultrasonic sensing element, wherein an elastic modulus of the portion is smaller than that of each ultrasonic sensing element, wherein the bonding member includes a spacer having an exterior size substantially equal to the thickness of the bonding member; the spacer is embedded in the bonding member; an elastic modulus of the spacer is larger than that of the bonding member; and the spacer and the bonding member are integrally formed.