The use of harmonics in ultrasound diffraction tomography [French]

摘要

In order to increase images resolution, this study present the use of the harmonics wave generated by ultrasonic distortion, in diffraction tomography imaging. The image reconstruction is based on Fourier diffraction theorem. The experimental setup is based on a 3 MHz circular transducer with 2 cm of diameter. Transmitted field is detected using a wide bandwith hydrophone. A comparison between the image of the fundamental wave with the images of the three successive harmonics waves shows that the quality of the image increases with the harmonic order. This improvement is due to beam directivity and secondary lobes attenuation. [References: 21]