FIELD: technical physics. SUBSTANCE: invention can be used to determine such physical parameters of metal melts as density and surface tension. The device comprises a base, a horizontal-type cylindrical electric furnace installed on it with a vacuum chamber and an end viewing window, a substrate for placing the melt sample under study, mounted on one of the ends of a horizontal position-adjustable rod located in the vacuum chamber, and a photodetector with a first lens installed on a base outside the electric furnace, coaxial with it and connected to a computer with a display. The device is equipped with a housing with a second lens and a replaceable light filter installed in it, which is located between the second lens and the end viewing window, and two adjustment elements are additionally installed on the base to adjust the position of the housing with the second lens relative to the photodetector. EFFECT: improved quality and accuracy of determining the parameters of the melts under study. 4 cl, 4 dwg.