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This paper presents new experimental results from a prototype Spectral LADAR, which combines active multispectral
and 3D time-of-flight point cloud imaging. The physical domain unification of these imaging modalities based on a
pulse modulated supercontinuum source enables substantially higher fidelity images of obscured targets compared to the
data domain fusion of passive hyperspectral cameras and conventional LADAR imagers. Spectral LADAR produces 3D
spectral point clouds with unambiguously associated 3D image points and spectral vectors, promoting improved object
classification performance in cluttered scenes. The 3D shape and material spectral signature of objects may be acquired
in daylight or darkness, behind common glass, and behind obscurants such as foliage and camouflage.
These capabilities are demonstrated by data obtained from test scenes. These scenes include plastic mine-like objects
obscured by foliage, distinction of hazardous explosives inside plastic containers versus innocuous decoy materials, and
3D spectral imaging behind ordinary glass windows. These scenes, at effective ranges of approximately 40 meters, are
imaged with nanosecond-regime optical pulses spanning 1.08 μm to 1.62 μm divided into 25 independently ranged
spectral bands. The resultant point cloud is spectrally classified according to material type.
In contrast to other active spectral imaging techniques, Spectral LADAR is well suited to operate at high pixel and frame
rates and at considerable stand-off distances. A combination of favorable attributes, including eye safe wavelengths,
relatively small apertures, and very short (single pulse) receiver integration time, bear the potential for this technique to
be used on robotic platforms for on-the-move imaging and high area coverage rates.
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