Novel results in short-range visualization and vision systems based on gated imaging

摘要

Visibility enhancement using gated images has been known for at least 20 years. The majority of gated imaging systems are used to enhance human vision under extremely difficult conditions (fog, turbid water, strong ambient light, etc.). In most of the reported applications the intended ranges of gated-imaging systems are rather long so that a simplified model of gated imaging can be used. Moreover, no attempts have been reported on methods more sophisticated than just capturing images using gated imaging. In this paper, we present selected results expanding areas of typical applications. First, we briefly discuss and explain the theory of short-range gated imaging. In vision-related applications, short-range gated imaging is needed only in high turbidity conditions so that we focus on gated imaging in highly turbid media. Secondly, we propose a technique for automatic image fusion using a sequence of gated images captured by a precisely controlled pulsed laser. The fusion of several images can provide good quality of visualization over a wide range of depths. A feasibility-study system build using this principle will be briefly discussed. We believe that the proposed methods are a significant step towards system capable of providing visibility in extremely difficult scenarios (e.g. inspecting areas of turbulent liquids, seeing through almost non-transparent liquids, etc.).