TEMPERATURE MEASURING METHOD OF RADIATION OF INFRARED RAY

摘要

PURPOSE:To obtain the temperature of an object to be measured by detecting the energy of infrared rays reflected from the surface of the object to be measured, and comparing it with the energy of reference infrared rays radiated from a black body furnace to calculate it. CONSTITUTION:Infrared detectors 30A-30G which detect the energy of reflected infrared rays which are radiated from a black body furnace 10 and are reflected on the surface of an object 14 to be measured are so arranged that detectors 30B-30G are placed at equal intervals and at equal angles around the infrared detector 30A, and a comparator 32 is provided which selects a maximum energy from reflected infrared rays N2a-N2g detected by infrared detectors 20A-30G and inputs it as a true energy due to the object 14 to be measured to a signal processing part 20. A temperature t2 obtained in an operating part 22 on a basis of an equivalent signal Pb of reference infrared rays Nb and a measured value signal P2 obtained by processing an output signal, which corresponds to the maximum energy which is detected by infrared detectors 30A-30G and is selected by the comparator 32, in a signal processing part 20 is the temperature of the object 14 to be measured. The influence due to the directivity of reflection upon the measured value is compensated to measure accurately the temperature of the object 14 to be measured in a low-temperature region without being influenced by the directivity of reflection of infrared ray.