NARCISSUS CORRECTING CIRCUIT AND NARCISSUS CORRECTING METHOD IN INFRARED THERMAL IMAGE DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a means to suppress narcissus which appears in a thermal image in an infrared thermal image device without specially modifying the configuration of an optical system. ;SOLUTION: A screenful of infrared detection signals 105 at the time of observing an open-hearth blackbody furnace at a constant temperature is stored in a memory 12 via a bus switch 13. The value of a single pixel of an area without so-called narcissus in the infrared detection signals 105 is set in a bias circuit 14. Next to this, the bus switch 13 is selected to connect the data bus 112 of the memory 12 to a terminal b of an adding-subtracting circuit 15. A screenful of the infrared signals of the open-hearth blackbody furnace is read from the memory 12 and inputted to the terminal b as data B. The infrared detection signals 105 of an object whose temperature distribution is to be observed are inputted to a terminal a of the adding-subtracting circuit 15 as data A. The value of the pixel set in the bias circuit 14 is inputted to a terminal c of the adding-subtracting circuit 15 as data C. The infrared detection signals 115 from which narcissus are removed are obtained by performing the calculation of the formula; Y=A+C-B, by the adding-subtracting circuit 15.;COPYRIGHT: (C)1998,JPO