Emission of optical radiation by the process of thermal radiation.
Thermal radiation is electromagnetic radiation originating in the thermal motions of particles of matter (atoms, molecules, ions, etc.). All matter above the temperature of absolute zero emits thermal radiation. Objects around room temperature emit mainly infrared radiation. Objects at temperatures higher than some 800 K also emit electromagnetic radiation in the visible area.
Thermal Light Radiators
Sun that generates light by its hot plasma with a temperature of around 6,000 K
Glowing coal and red hot horseshoe with a temperature of around 1,000 K
Torches, oil lamps, candles, and gas lamps with temperatures of around 2,000 K
Carbon-arc lamps with temperatures of up to 5,000 K
Old-fashioned chemical flash bulbs with temperatures of around 4,000 K
Incandescent lamps with temperatures of 2,700 K
Halogen incandescent lamps with temperatures of 2,900–3,200 K
Black body radiator
Black Body Radiator
A black body...