CALCULATION OF THE INFLUENCE OF NARCISSUS EFFECT IN COOLED THERMAL IMAGING DEVICES2 views
Keywords:Cooled thermal imaging device; Optical system; Narcissus effect; NITD.
In this paper the theorical basics and the calculation method of the influence of Narcissus effect in cooled thermal imaging devices are presented. This effect was calculated quantitatively for each surface and the whole optical system based on the NITD parameter and Zemax software application working in the non-sequential mode. Calculation results for a typical optical system show that the spurious temperature difference is about 280 mK, many times greater than the sensitivity of the detector, greatly affecting the image quality of cooled thermal imaging devices. This calculation method allows to analyze the influence of the Narcissus effect during the design of the cooled thermal imaging devices.
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