A high efficiency adaptive ultrasonic array imaging method with sensitivity correction for curved structures

The adaptive ultrasonic array imaging can be used for defects detection with unknown sample profile. To solve the problems of low computational efficiency and difficult quantitative evaluation in detection, this paper presents a high efficiency adaptive ultrasonic array imaging method with sensitivity correction. For surface reconstruction, the vector coherence technique has been used to correct the plane wave imaging of sample surface with single emission, which improves the imaging quality and efficiency. A robust fitting method is proposed based on Random Sample Consensus algorithm to reconstruct the surface after the surface pixel recognition. To reduce the beam path calculation time, a prediction search method is developed, whose time consumption is reduced by 97.2 % compared with the global traversal method with the same results. The sensitivity correction algorithm is proposed based on the ultrasonic propagation model, which makes the amplitude difference of defects in different regions is less than 0.8 dB.