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Comb-calibrated laser ranging for three-dimensional surface profiling with micrometer-level precision at a distance



Esther Baumann, Fabrizio R. Giorgetta, Jean-Daniel Deschenes, William C. Swann, Ian R. Coddington, Nathan R. Newbury


Non-contact surface mapping at a distance is interesting in diverse applications including industrial metrology, manufacturing, forensics, and artifact documentation and preservation. Frequency modulated continuous wave (FMCW) laser detection and ranging (LADAR) is a promising approach since it offers shot-noise limited precision/accuracy, high resolution and high sensitivity. We demonstrate a scanning imaging system based on a frequency-comb calibrated FMCW LADAR and real-time digital signal processing. This system can obtain three-dimensional images of a diffusely scattering surface at stand-off distances up to 10.5 m with sub-micrometer accuracy and with a precision below 10 µm, limited by fundamental speckle noise. Because of its shotnoise limited sensitivity, this comb-calibrated FMCW LADAR has a large dynamic range, which enables precise mapping of scenes with vastly differing reflectivities such as metal, dirt or vegetation. The current system is implemented with fiber-optic components, but the basic system architecture is compatible with future optically integrated, on-chip systems. Work of the US government and not subject to copyright.
Applied Optics


LADAR, FMCW, comb, speckle


Baumann, E. , Giorgetta, F. , Deschenes, J. , Swann, W. , Coddington, I. and Newbury, N. (2014), Comb-calibrated laser ranging for three-dimensional surface profiling with micrometer-level precision at a distance, Applied Optics, [online], (Accessed May 20, 2024)


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Created October 6, 2014, Updated November 10, 2018