Experimental system for the study of the directional thermal emission of natural surfaces

A new automatic experimental system was designed to improve the accuracy of multidirectional thermal infrared measurements. This experimental system mainly consists of two identical thermal cameras operating at 8-13 mu m, one metal ring to keep the constant view area for different view angles and a goniometer, which is composed of: (1) a semicircular roadway of 2 m diameter to change the observation angle in the azimuth direction; (2) an elevator of 1 m height to adjust the measuring level to the target level; (3) a rotating arm equipped with one thermal camera for changing the observation angle in the zenith direction; and (4) a fixed arm equipped with another thermal camera to record at n…