Active stabilization of ESPI systems for applications under rough conditions

A method for the active stabilization of an out-of-plane electronic speckle pattern interferometer (ESPI) is presented. A compact Michelson interferometer is adapted to the ESPI head to determine the relative motion between the ESPI and the object. The signal of the Michelson interferometer is prepared by a microcontroller and supplied as an addition signal to the phase shifting unit of the ESPI. The presented solution is a practical method for applications with real-time ESPI. It increases the potential of ESPI especially for applications outside of an optical laboratory under rough conditions.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.