Image Formation in Highly Turbid Media by Adaptive Fusion of Gated Images

A visibility enhancement technique for highly-scattering media (e.g. turbid water) using an adaptive fusion of gated images is proposed. Returning signal profiles produced by gated imaging contain two peaks: the backscattering peak followed by the target-reflected peak. The timing of the backscattering peak is determined by the laser pulse parameters, while the location of second peak depends on the target distance. Thus, a sequence of gated images ranged over a variety of distances can be used to visualize scenes of diversified depths. For each fragment of the scene, the gated image containing the maximum signal strength (after ignoring the backscattering peak) is identified to form the corresponding fragment of the fused image. This unique capability of capturing both visual and depth information can lead to development of fast and robust sensors for vision-guided navigation in extremely difficult conditions.