Simple optical method for measuring the temperature of an incandescent filament under vacuum

A new optical method is proposed for measuring the temperature of an incandescent filament under vacuum. The method is based on measurement of the intensity of thermal radiation at one fixed wavelength while varying the magnitude of the filament current, without using a calibrated reference radiator. The method has been experimentally tested. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 3, pp. 414–416, May–June, 2006.