The difference between infrared Photography and Infrared Heat.
Infrared photography uses the Infrared wavelength, a wavelength longer than that of visible light, but shorter than that of microwaves. The name means “below red” (from the Latin infra, “below”), red being the color of visible light with the longest wavelength. Infrared radiation has wavelengths between about 750 nm and 1 mm, spanning five orders of magnitude.
Infrared heat that is used in asphalt paving uses Infrared radiation and is popularly known as “heat” or sometimes “heat radiation”.
Many people incorrectly attribute all radiant heating to infrared light and/or to all infrared radiation to being a result of heating. This is a widespread misconception, since light and electromagnetic waves of a wavelength frequency.
Infrared Heat is energy in transient from thermal conduction or thermal convection, and is used to heat shops, set paint and repair asphalt.