Patent ID: 8559696

Claim:
An imaging method of a structure defect that detects a defect such as a crack contained in a structure, having an ultrasonic transmitter that radiates burst ultrasonic waves composed of sine waves with a predetermined cycle number and an array receiver having a plurality of reception sensor elements, comprising: in first arrangement in which said ultrasonic transmitter and said array receiver are arranged at predetermined positions with respect to said defect, a first reception process of receiving scattered waves from said defect of said burst ultrasonic waves radiated from said ultrasonic transmitter to said structure by said array receiver so as to obtain a first reception signal; a first imaging process in which said first reception signal is subjected to a band-pass filter that passes a specific frequency component and is shifted by different time according to the position of each of the reception sensor elements of said array receiver and then, added so as to obtain a first processing signal, and a first image of said defect is obtained on the basis of said obtained first processing signal; in second arrangement in which at least one of the positions of said ultrasonic transmitter and said array receiver with respect to said defect is different, a second reception process of receiving the scattered waves from said defect of said burst ultrasonic waves radiated from said ultrasonic transmitter to said structure by said array receiver so as to obtain a second reception signal; a second imaging process in which said second reception signal is subjected to said band-pass filter and is shifted by different time according to the position of each of the reception sensor elements of said array receiver and then, added so as to obtain a second processing signal, and a second image of said defect is obtained on the basis of said obtained second processing signal; and an extraction process of extracting a common portion of said first image and said second image.