Two-Dimensional Reconstructed Image of a Subsurface Structure Using Continuous Scanned Photothermal Imaging  

作　　者：Moojoong KIM Hyunjung KIM 

机构地区：[1]Research Institute for Science and Engineering,Waseda University,Tokyo 169-8555,Japan [2]Department of Mechanical Engineering,Ajou University,Suwon 16499,Republic of Korea

出　　处：《Photonic Sensors》2025年第2期1-12,共12页光子传感器(英文版)

基　　金：supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education,Republic of Korea(Grant No.NRF-2015R1D1A1A01060704);Japan Society for the Promotion of Science(JSPS)KAKENHI,Japan(Grant No.JP23K13269).

摘　　要：This study presents the two-dimensional(2D)image of a subsurface structure reconstructed using an imaging method based on the photothermal effect.The photothermal imaging method is based on the deflection method using two lasers:pump and probe lasers.A continuous scanning technique is proposed for 2D(x-and y-directions)surface scanning.The continuous scanning method is compared with the conventional point-by-point scanning technique,and a low-pass fast Fourier transform filter and a Marr-Hildreth detector are found to produce significant results.The photothermal imaging method with continuous 2D surface scanning is performed on three copper-resin double-layer samples with different subsurface structures.The subsurface structures of the copper-resin double-layer samples comprise a square block of 5×5 mm^(2) area and blocks shaped as the alphabet letters“T”and“F”.The letters are 3 mm wide and 10×13 mm^(2) in area.All three shapes are 1 mm thick and located at a depth of 0.5 mm from the surface of the copper block.The reconstructed photothermal images show an absolute error within 0.122 mm compared with the actual subsurface structure,equivalent to a 2.3%relative error.

关 键 词：Photothermal effect photothermal imaging nondestructive test RECONSTRUCTION VISUALIZATION TOMOGRAPHY 

分 类 号：TN249[电子电信—物理电子学] O439[机械工程—光学工程]