A high resolution approach for nonlinear sub-harmonic imaging

CS Park, JW Kim, S Cho, D Seo - NDT & E International, 2016 - Elsevier
Nonlinear sub-harmonic phased array imaging is used to visualize closed cracks. Sub-
harmonic imaging has broader beam width than that of input frequency imaging due to its …

Image enhancement for sub-harmonic phased array by removing surface wave interference with spatial frequency filter

CS Park, JW Kim, SH Cho, DC Seo - Journal of the Korean Society …, 2014 - koreascience.kr
Closed cracks are difficult to detect using conventional ultrasonic testing because most
incident ultrasound passes completely through these cracks. Nonlinear ultrasound …