Infrared vidicon tubes of the type N 214 from Hamamatsu have widespread use for various measurements in the field of optical communication, in spite of their severe drawbacks such as poor stability and low accuracy. Usually, they interface with a desktop computer as a controller, so that the influences of dark current, shading, and nonlinearity may be corrected. With a specially designed computerhyphen;controlled lamp and an optimized algorithm, it is possible to calibrate the vidicon very fast. Dark current, shading, and nonlinearities result in errors less than 9percnt; and are mainly determined by the strong thermal drift of the tube. Because of the leasthyphen;squareshyphen;fitting technique, the calibration is very noise insensitive.
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