a device in which the radiant energy from a source is focused by a reflector system, on an area usually 1–30 mm in diameter or, in large furnaces, up to 350 mm in diameter. As a result, a temperature of 1000°–5000°C may be reached in the area.
Optical furnaces are widely used for research on the physico-chemical properties of materials at high temperatures and the effect of intense radiant fluxes on materials and organisms, and also for such operations as melting under especially clean conditions, welding and soldering refractory materials, growing of single crystals, and refining nonferrous metals. Optical furnaces are classified according to the source of radiant energy: solar furnaces, in which the energy of solar radiation is used, and furnaces with artificial energy sources (incandescent lamps, graphite heaters, arc lamps, superhigh-pressure xenon gas-discharge tubes, and plasma radiators). The design of an optical furnace depends on its functions; in all cases optical furnaces include a radiation source, a reflector unit, a radiant flux regulator that is used to change and maintain the temperature, and a working chamber.
REFERENCEOpticheskie pechi. Moscow, 1969.
V. M. TYMCHAK