The multi-mode plane wave imaging in the Fourier domain: Theory and applications to fast ultrasound imaging of cracks. (March 2020)

• Record Type: Journal Article
• Authors: Merabet, L.; Robert, S.; Prada, C.
• Is Part Of: NDT & E international. Volume 110(2020)
• Publication Date: 2020-03
• Subjects: Ultrasonic array -- Multi-mode imaging -- Plane wave -- Fourier-domain reconstruction; Nondestructive testing -- Periodicals; Contrôle non destructif -- Périodiques; Electronic journals; 620.1127
• DOI: 10.1016/j.ndteint.2019.102171
• Languages: English
• ISSNs: 0963-8695

Abstract

Abstract: The Total Focusing Method (TFM) was generalized about ten years ago to form images with complex ultrasound paths involving reflections and mode conversions at the interfaces of a testing sample. The resulting multi-mode imaging allows to fully image the face of a crack-type defect. More recently, the Plane Wave Imaging (PWI) was revisited to perform multi-mode reconstructions with a small number of transmissions compared to the TFM. In order to further accelerate the imaging process, we propose here to combine plane wave emissions with a fast reconstruction algorithm in the Fourier domain. The method was developed in medical imaging with the pioneering works of J.- Y. Lu, and was studied in a recent paper to form images in solids with direct reconstruction modes. In the present paper, the theory is extended to various reconstruction modes (half-skip and one-skip modes with/without mode conversions), and the imaging method is evaluated with experimental results in a sample featuring different planar defects. We show that the method provides multi-mode images equivalent to those computed with the time-domain PWI, while reducing the computation times by a factor up to 13.