Some applications of digital speckle pattern interferometry (DSPI)

Electronic/digital speckle pattern interferometry (ESPI/DSPI) is a promising field having a variety of applications in the measurement of displacement/deformation, vibration analysis, contouring, non-destructive testing, etc. The capability of ESPI/DSPI in displaying correlation fringes on a TV monitor is one of its distinct features. It serves as a convenient alternative for holographic techniques and hence it is often commercially referred to as `TV holography´. The authors describe the DSPI setup developed at IIT, Madras and some of the applications for which it has been used