from Wikipedia, Incandescent light bulb
So "incandescent" bulbs emit light--including red light--but also invisible "near-infrared" wavelengths, which produce heat.
"Near-infrared." That's not the same as "infrared."
But in the same Wiki article they have a thermal image of an incandescent bulb
with this note below:
This says incandescent bulbs emit "infrared" wavelengths.
Not just "near-infrared" wavelengths are noted in the same Wiki entry.
Damn confusing.
"An electric current heats the filament to typically 2,000 to 3,300 K (3,140 to 5,480 °F)), well below tungsten's melting point of 3,695 K (6,191 °F). Filament temperatures depend on the filament type, shape, size, and amount of current drawn. The heated filament emits light that approximates a continuous spectrum. The useful part of the emitted energy is visible light, but most energy is given off as heat in the near-infrared wavelengths."
So "incandescent" bulbs emit light--including red light--but also invisible "near-infrared" wavelengths, which produce heat.
"Near-infrared." That's not the same as "infrared."
But in the same Wiki article they have a thermal image of an incandescent bulb
with this note below:
"Thermal image of an incandescent bulb. Much of the energy is emitted as infrared. The IR heats the glass, which conducts the heat to the surrounding air, producing convection."
This says incandescent bulbs emit "infrared" wavelengths.
Not just "near-infrared" wavelengths are noted in the same Wiki entry.
Damn confusing.