Differential temperature measuring radiometer

Abstract

In a double thermal coupled radiometer for preferable use with a centrifuge, an improved radiometer configuration is disclosed. The isothermal radiometic system improved is of the double junction variety (preferably copper-constantan-copper) and includes a black body housing defining a central concavity. The central concavity has a black body disk at the bottom thereof. The disk is preferably suspended by a copper and a constantan wire with one junction formed on the surface of the disk and the other junction formed on the surface of the housing. The improvement includes a plurality of and preferably three annular baffles defining central, circular and preferably concentric opening. These baffles are lodged in the opening of the housing above the mounted radiometer disk. The annular baffles on the side towards the radiation sources are coated as a black body so as to increase the thermal coupling of the black body housing to the ambient being radiometically observed. The baffles on the side away from the radiation source and exposed to the radiometer disk are reflectively coated to decrease further any couple between the radiometer disk and the black body housing. The combination of the baffles and the disk combine to give the radiometer a small field of view which permits radiometic thermal measurement of a small solid angle and ignores the remainder of the environment. Preferred use of the radiometer in looking at a centrifuge rotor is disclosed.