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The present work describes the modeling and the simulation of a concept of novel sensor-single tube color image intensifier intended for direct observation of the night side of the Earth or other planets in the visible range of the spectrum from orbit, or as airborne sensor or as color image preamplifiers for color CCD sensors. The color image sensor consists of an objective and microchannel tube which contains an input multielement color filters pattern, matched and registered with output multielement color filters pattern. Input/output color filters patterns, which determine the spatial sampling of the image, were organized both in hexagonal RGB mosaic and in RGB stripes configuration. The present work is aimed at describing the basic theoretical models for simulation and analysis of the color image sensor including quantification and optimization of its performance. The basic models include the major color intensifier parameters, namely, spectral characteristics of the color filter elements, their size and spacing; spectral characteristics of the photocathode and phosphor; MCP's pore size, center-to-center spacing and gain; voltages and distances of spacing photocathode -- MCPin and MCPout -- screen; tolerance of registration of input- output filters, etc. For a number of technologically achievable parameters it is shown that: (1) the resolution of the device, based on the Nyquist frequency for hexagonal mosaic filter configuration can reach approximately 20 color (line pairs)/mm; for stripe filter configuration it can reach approximately 30 color (line pairs)/mm along stripes and approximately 10 color (line pairs)/mm across stripes with adequate MTF; (2) the light non-uniformity is less than 5% which is insignificant; (3) realistic set of filters provides a good color transformation -- compatible to the transformation in color CRT displays. The model also describes the color edge transformation. As it was shown, cross-talk level in single basic color element from neighboring elements is about 6%, and its influence is expressed in moving the color coordinates of a uniform color on the tube's output toward the 'white point' on the CIE chromaticity diagram. Modeling showed that color imaging can be achieved at very low light levels with good color resolution and color preservation. The first color images were successfully obtained from a prototype, demonstrating that the proposed concept indeed produces a color vision image intensifier device with good color imaging abilities. The computer simulation agrees well with photometrical and colorimetrical parameters of the first workable prototypes.
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