The feasibility of two-beam speckle interferometry for the study of time-varying mechanical deformation of diffusely reflecting bodies is demonstrated. A sequence of speckle patterns produced by a vibrating cantilever beam was recorded photographically by means of a high-speed camera. These speckle photographs were subsequently digitized using a CCD camera for input into an image processing computer. By gray-level subtraction of carefully registered pairs of speckle images, fringes corresponding to the relative surface displacements were obtained. A sequence of these fringe patterns was reconstructed to obtain the time-history of deformation. These are compared with time-frozen (strobed) patterns for the same body.

Date Published: 1 December 1991
PDF
Proc. SPIE 1554, Second International Conference on Photomechanics and Speckle Metrology, (1 December 1991); doi: 10.1117/12.49505

Published in SPIE Proceedings Vol. 1554:
Second International Conference on Photomechanics and Speckle Metrology
Fu-Pen Chiang; Fu-Pen Chiang, Editor(s)