ULTRASONIC MEASURING DEVICE, ULTRASONIC SENSOR FOR USE IN THE SAME, AND ULTRASONIC MEASURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide an ultrasonic measuring device suited for detecting a flaw in a depth of a thick plate, capable of enlarging the opening of a sensor, to provide an ultrasonic sensor for use in the same, and to provide an ultrasonic measuring method. SOLUTION: The internal circumference 401M of a two-dimensional array sensor 401B is located at a point that a distance between the centers of gravity locations of neighboring ultrasonic vibration elements is within a distance L0 that does not produce a noise (grating lobe). The external circumference 401N includes a distance between the centers of gravity locations of neighboring ultrasonic vibration elements which is located within the distance which does not produce noise and one which is located over the distance which produces a noise. A using element selection circuit 403C selects all ultrasonic vibration elements in the internal circumference 401M and ultrasonic vibration elements of the ultrasonic vibration elements on the external circumference, located at a point that a distance between the centers of gravity locations of neighboring ultrasonic vibration elements is within the distance that does not produce a noise in the transmitting and receiving direction that the transmitting and receiving direction of an ultrasonic wave is projected to the surface of the array sensor. COPYRIGHT: (C)2011,JPO&INPIT