Digital speckle interferometry: some developments and applications for vibration measurement in the automotive industry

This paper presents an overview of some recent progress in digital speckle interferometry and its application for vibration measurement in the automotive industry. It describes three methods to generate raw vibration fringe patterns with better quality; provides speckle averaging, phase shifting, and phase reconstruction iteration procedures to produce a high-quality and noise-free fringe pattern; illustrates one single setup for measuring both vibration deformation and geometric shape of an object; and demonstrates how powerful this tool is for whole vehicle modal survey, interactive design optimization, CAE model correlation, and nondestructive testing. Finally, areas for further development are suggested. (C) 1998 Society of Photo-Optical Instrumentation Engineers. [S0091-3286(98)00905-2].