The Partial Radiation Pyrometer, ‘PYROPTO’ is a disappearing filament Optical Pyrometer, suitable for measuring high temperature of incandescent objects, in annealing and hardening furnaces, in firing kilns, for measuring the temperature of molten and flowing metal or glass as well as incandescent blocks during forging, pressing or rolling. The temperature measurement makes use of comparison between the brightness of an electrically heated and calibrated incandescent filament(reference light bulb) in Pyropto and that of the object to be measured. The special advantage offered by the PYROPTO is the light weight of the instrument which houses all components of the complete measuring equipment. Thus, it can be transported by means of carrying strap from place to place without any inconvenience. Due to its appropriate design, the simple measuring principle used is the convenience of its operation. High accuracy measurements can also be carried out even by less skilled operators. An additional advantage is the suitability for carrying out measurements on very small surfaces of down to 2 mm diameter and a measuring distance of 60 cm. Every PYROPTO has two measuring ranges.