Share Email Print

Proceedings Paper

New shearing setup for simultaneous measurement of two shear directions
Author(s): Thorsten Siebert; Bernhard Schmitz
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Shearography is a full field interferometric technique for the measurement of small deformation gradients. The main fields of application are non-destructive testing in quality control and material inspection. In both cases the direction of the deformation gradient plays a major role. We present a new image shearing speckle pattern interferometer set-up for simultaneous measurement of two independent deformation gradients equivalent to two shear directions. Herein, we use the polarization effect to separate the two directions. Based on a Michelson interferometer, we placed in one arm an additional polarization beamsplitter (PBS) and an additional mirror. The two orthogonal polarized images can be separated by a further PBS and simultaneously captured by a second camera. Substituting the second PBS with a rotatable polarizator and using only one camera, both sheared images can be recorded in rapid succession. We make use of a liquid crystal cell as a fast rotating polarizator and demonstrate the utility of this new concept with measurements in an industrial environment on a tensile testing machine.

Paper Details

Date Published: 25 March 1999
PDF: 6 pages
Proc. SPIE 3637, Practical Holography XIII, (25 March 1999); doi: 10.1117/12.343778
Show Author Affiliations
Thorsten Siebert, Univ. Ulm (Germany)
Bernhard Schmitz, Univ. Ulm (Germany)

Published in SPIE Proceedings Vol. 3637:
Practical Holography XIII
Stephen A. Benton, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?