Experimental strain analysis by DSPI - applications

During the last years digital Speckle pattern interferometry (DSPI) has been developed to become a convenient measuring tool and a variety of engineering applications has proved its usefulness. The following features characterize this optical method: - interferometric sensitivity (Lambda 450...850 nm), - quantities: deflection, strain bigger than 10high-6, - real-time capability for qualitative analyses, - fully automatic evaluation by digital image processing, - wide field of application: samples, components of different kind of materials, - use at high temperatures. The main components of a DSPI- system, as CCD-camera, laser, beam splitter and phase shifter take advantage from general developments on the opto-electronic market and the progress in this field allows to design new interferometers. So, minimizing size and automating fringe analysis by digital image processing yield more flexible and robust systems than hitherto existing.