A common problem during study of, for instance, tensile tests with interferometers is that the sample moves too much so that the speckles decorrelate and no phase information is obtained. Two ways to overcome this problem are compared: a combination of speckle interferometry and speckle correlation and a method in which the reference image is updated during the experiment. The comparison shows that both techniques can be used to measure the deformation of an object even if it is exposed to rigid body motions. Both techniques are applied to measurements of microscale deformation fields of an adhesive joint in a carbon-fiber epoxy composite.
© 2004 Optical Society of America
(120.3180) Instrumentation, measurement, and metrology : Interferometry
(120.3940) Instrumentation, measurement, and metrology : Metrology
(120.4290) Instrumentation, measurement, and metrology : Nondestructive testing
(120.6160) Instrumentation, measurement, and metrology : Speckle interferometry
Angelica Svanbro, "In-Plane Dynamic Speckle Interferometry: Comparison between a Combined Speckle Interferometry/Speckle Correlation and an Update of the Reference Image," Appl. Opt. 43, 4172-4177 (2004)