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A working handheld 3-D diffraction range finder, nicknamed Moly, is demonstrated. This prototype is distinguished by a far-field magnification feature that is made possible by use of chirped frequency diffraction grating optics that reverse the perspective foreshortening typical of conventional triangulation range finders. This new type of 3-D profilometer illuminates its target with a collimated laser projector that produces a rectangle-shaped sheet of light of uniform width at all working distances. Moly also employs dual magnetic wave detectors to facilitate freedom of movement for both the digitizing instrument and the subject. The instrument was designed primarily to digitize human faces and figures for applications in art and medicine.


Copyright 2000 Society of Photo-optical Instrumentation Engineers (SPIE)

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Optical Engineering

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Ditto, Tom, and Douglas A. Lyon. "Moly: a prototype handheld three-dimensional digitizer with diffraction optics." Optical Engineering 39, no. 1 (2000): 69-78.



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