Digital Speckle Pattern Interferometry (DSPI) has been applied to measure shape of solid rough objects. A two wavelength setup with one single recording has been applied. Spatial Phase Shifting techniques, with different carrier fringes for each wavelength, have been used in order to produce a spatial multiplex. Selecting each aperture image in the Fourier plane, the amplitude and the phase of the object beam is obtained for each wavelength. The subtraction of those waves produces a wrapped phase map that can be considered a contour line map for a synthetic wavelength. The technique has been applied in different material and the visibility of the fringes is observed. The possibilities and limits of the technique have been analyzed.

Date Published: 18 August 2014
PDF: 7 pages
Proc. SPIE 9204, Interferometry XVII: Advanced Applications, 92040B (18 August 2014); doi: 10.1117/12.2061889

Published in SPIE Proceedings Vol. 9204:
Interferometry XVII: Advanced Applications
Cosme Furlong; Christophe Gorecki; Peter J. de Groot; Erik L. Novak, Editor(s)