Solid-state color night vision - Fusion of low-light visible and thermal infrared imagery

We describe an apparatus and methodology to support real-time color imaging for night operations. Registered imagery obtained in the visible through NIR band is combined with thermal IR imagery by using principles of biological opponent-color vision. Visible imagery is obtained with a Gen III image intensifier tube fiber-optically coupled to a conventional CCD, and thermal IR imagery is obtained by using an uncooled thermal imaging array. The two FOVs are matched and imaged through a dichroic beam splitter to produce realistic color renderings of a variety of night scenes. We also demonstrate grayscale and color fusion of intensified-CCD/FLIR imagery. Progress in the development of a low-light-sensitive visible CCD imager with high resolution and wide intrascene dynamic range, operating at 30 frames per second, is described. Example low-light CCD imagery obtained under controlled illumination conditions, from full moon down to overcast starlight, processed by our adaptive dynamic-range algorithm, is shown. The combination of a low-light visible CCD imager and a thermal IR microbolometer array in a single dualband imager, with a portable image-processing computer implementing our neuralnet algorithms, and color LCD, yields a compact integrated version of our system as a solid-state color night-vision device. The systems described here can be applied to a large variety of military operations and civilian needs. (Author)