Abstract
Quantitative measurements of shapes, displacements and deformations of opaque objects, as well as of refractive properties of transparent media, through spatial and temporal fringe patterns analysis is done by applying two basic techniques. The first one is the phase modification technique. The second one is the Fast Fourier Transform technique (FFT), assisted by some sort of heterodyning. FFT is also the choice for a single frame, not-modified, interferogram analysis. In this case however, because the lack of a spatial carrier, the sign of the phase cannot be determined. A solution to this problem is a technique that requires only two phase-shifted interferograms. In this paper we propose a holographic interferometry method based on wavelength multiplexing in which no spatial carrier neither second, phase shifted interferogram is required. Using the Lippmann-Denisyuk single beam holographic setup, an interferogram form a deformable object is recorded with multiple laser wavelengths in a panchromatic emulsion. A reconstruction of the 3D object in colors is observed, superimposed with a multicolor fringe pattern. The object phase is then computed from the multiple single-wavelength fringe patterns, allowing the measurement of the object deformation. This work is aiming at quantitative analysis of highly dynamic objects.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
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