Nondestructive material characterization using electronic speckle pattern interferometry

Electronic speckle pattern interferometry (ESPI) has developed from the experimental substitution of classical interferometry to become a quite useful tool not only in research but also in industry. The rapid development of computer techniques and digital imaging in combination with the miniaturization of the optical equipment led to compact and accurate measuring solutions that opened new applications which had not been anticipated before. Overcoming the limitations of classical holographic interferometry, ESPI system are now easily handled as portable measuring system in almost any place. This paper gives a brief summary of the application of the ESPI technique in the field of nondestructive material characterization. Covering static as well as dynamic techniques, typical applications are shown. An assessment of the capabilities of ESPI systems is provided as well as an outlook for further development.