Measurement of Liquid Surface Temperature by a Infrared Radiation Thermometer

Abstract

A method for measuring liquid. surface temperature by a infrared radiation thermometer is described. When the temperature is measured through a glass plate, following corrections are required: (1) transmissivity of the glass plate, (2) Thermal radiation from the glass plate, and (3) thermal radiation from the room walls which reflects at the glass plate. In this study, a correction method of the above effects is presented, and is confirmed by the experiment. The surface temperature of water was measured through a BaF₂ plate in the range of 40∼90°C. The accuracy of the measurements was within ±0.5°C.