The European Defence Agency (EDA) launched the Active Imaging (ACTIM) study to investigate the potential of active
imaging, especially that of spectral laser imaging. The work included a literature survey, the identification of promising
military applications, system analyses, a roadmap and recommendations.
Passive multi- and hyper-spectral imaging allows discriminating between materials. But the measured radiance in the
sensor is difficult to relate to spectral reflectance due to the dependence on e.g. solar angle, clouds, shadows... In turn,
active spectral imaging offers a complete control of the illumination, thus eliminating these effects. In addition it allows
observing details at long ranges, seeing through degraded atmospheric conditions, penetrating obscurants (foliage,
camouflage...) or retrieving polarization information. When 3D, it is suited to producing numerical terrain models and to
performing geometry-based identification. Hence fusing the knowledge of ladar and passive spectral imaging will result
in new capabilities.
We have identified three main application areas for active imaging, and for spectral active imaging in particular: (1) long
range observation for identification, (2) mid-range mapping for reconnaissance, (3) shorter range perception for threat
detection. We present the system analyses that have been performed for confirming the interests, limitations and
requirements of spectral active imaging in these three prioritized applications.