作 者: ;
机构地区: 南京大学物理学院近代声学教育部重点实验室
出 处: 《物理学进展》 1996年第3期439-449,共11页
摘 要: 光声热波成像作为一种扫描成像技术,由于无损和非侵入式引起很大的兴趣。由于热波是一种高衰减波,且波长短,现已成功地实现了对材料亚表面结构的分层成像。热波技术适合于对复合材料和多层结构进行评价和缺陷定征,特别适合于半导体材料和微电子器件的研究与分析。在热波成像技术中引入空间多道信号处理方法,使样品表面的入射光功率密度大大减小的情况下改善了信噪比。最近,新发展了热脉冲回波成像技术,用于评价飞机的胶接部分,结果表明,热波成像完全有可能对飞机在使用期的不同阶段进行分层检测。 Thermal wave imaging is one of scanning imaging techniques, and has attracted a great interest, because of its nondestructive, non-invasive and sometimes noncontact nature. Laminated imaging of the subsurface structures of materials has been successfully realized by this technique because thermal waves are heavily damped and have short wavelengths. Thermal wave techniques are suitable to evaluate and detect features in composite or multilayered materials, especially semiconductor materials and micro-electronic devices. The application of spatially multiplexed signal processing to the thermal wave imaging makes the incident optical density on the surface of the sample to be greatly reduced and the signal-to-noise ratio to be considerably improved. More recently, pulse-echo thermal wave imaging has been developed for evaluating the adhesively bonded structures of aircrafts. The results indicate that thermal wave imaging is capable of detecting disbond in all the stages of cycling.