The phenomenon of heat radiation is extremely common, and the heat radiation generated by the object at a low temperature is all infrared light, so the human eye cannot directly observe it. When heated to about 500 degrees, dark red visible light is produced, and as the temperature rises, the light becomes brighter and whiter. In the heat radiation source, the temperature is maintained by heating the filament for continued illumination. The energy supplied from the outside is balanced with the energy reduced by radiation while maintaining a certain temperature. When the radiator is at different heating temperatures, the peak wavelengths of the radiation are different, and the spectral energy distribution is also different. According to the above principle, the infrared light bulb made by special design and process has an infrared light component of up to 92-95%. The technical performance of this kind of infrared bulb produced abroad is: power 100 ~ 375W; power supply voltage 230 ~ 250V; service life 5000 hours, radiation angle 60 ~ 80 degrees.