A multi-axis heterodyne interferometer concept is under development for observations of five degrees of dynamicfreedom using a single illumination source. This paper presents a laboratory system that combines elements ofheterodyne Doppler vibrometry, holography, and digital image correlation to simultaneously quantify in-planetranslation, out-of-plane rotation, and out-of-plane displacement at the nanometer scale. The sensor conceptobserves a dynamic object by mixing a single optical field with heterodyne reference beams and collecting thesecombined fields at the image and Fourier planes, simultaneously. Polarization and frequency multiplexing areapplied to separate two segments of a receive Mach-Zehnder interferometer. Different optical configurations areutilized; one segment produces a focused image of the optical field scattered off the object while the other segmentproduces an optical Fourier transform of the optical eld scattered off the object. Utilizing the amplitude andphase from each plane allows quantification of multiple components of transient motion using a single, orthogonalbeam.
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