An infrared radiometry system using a PbSnTe infrared detector and two spherical concave mirrors coated with aluminum ($M_1:f = 100cm, F/# = 8.3, M_2:f = 25cm, F/# = 2.5$) is constructed.
Using this system, we measured the thermal radiation energy emitted from radiators of cone type under the same conditions in the temperature range of 20℃~50℃, where radiators are unpolished copper, aluminum foil, zerox carbon, and Eppley parsons Black Laquer. For Eppley Parsons Black Laquer used as a reference blackbody, the temperature resolution limit of this system is 0.15℃ in the temperature range of 20℃~50℃. Comparing the output signal voltage with that of the reference blackbody on the same variation of temperature of both, the emissivities of copper, aluminum, and carbon are measured as 0.622,0.209, and 0.959 respectively relative to the reference blackbody.
When the target moves continuously in the fixed radiometry system as scanning process, it is obtained the one dimensional analog voltage train produced by the target pattern. In the present work, we used a target pattern which consists of aluminum and Eppley Parsons Black Laquer to give a high contrast to the Image. The image pattern thus obtained shows a reasonable agreement with the original target pattern except the bluring of the boundaries caused by the spatial resolution limit of the optical system.
