Patent ID: 7565842

Claim:
An ultrasonic receiver, comprising: a first horn having a first large opening which is an ultrasonic incidence end and a first small opening which is an ultrasonic outgoing end; a second horn having a second small opening which is an ultrasonic incidence end and a second large opening which is an ultrasonic outgoing end, the second horn being located such that the first small opening of the first horn and the second small opening of the second horn face each other, and such that a first propagation direction of an ultrasonic wave propagating in the first horn and a second propagation direction of the ultrasonic wave propagating in the second horn match each other; and at least one ultrasonic receiver main body provided between the first small opening of the first horn and the second small opening of the second horn, the ultrasonic receiver including a surface parallel to the first propagation direction and detecting the ultrasonic wave which has propagated in the first horn and then is incident on the parallel surface; wherein: a space in the first horn in which the ultrasonic wave propagates has a cross-sectional area, vertical to the first propagation direction, which decreases from the first large opening toward the first small opening; and a space in the second horn in which the ultrasonic wave propagates has a cross-sectional area, vertical to the second propagation direction, which increases from the second small opening toward the second large opening.