Imaging method and device based on ultrasonic Lamb wave defect detection

The invention relates to an imaging method based on ultrasonic Lamb wave defect detection, the method comprises the following steps: acquiring defect echo signals of a to-be-detected plate-shaped structure, the defect echo signals at least comprising a first mode Lamb wave echo signal and a second mode Lamb wave echo signal; performing focusing processing on the Lamb wave echo signal of the first mode and the Lamb wave echo signal of the second mode, and determining a focused echo signal; based on the focusing echo signal, determining a first distance, wherein the first distance represents the distance between the position of the sensor corresponding to the defect echo signal and the position of the defect; and determining a defect detection image of the to-be-detected plate-shaped structure based on the first distance corresponding to the N defect echo signals. According to the imaging method based on ultrasonic Lamb wave defect detection, high-precision imaging of defects in the two-dimensional plate-shaped