Understanding IR
IR rejection is a commonly misunderstood property that can create confusion. Near IR, Infrared solar energy is the area of the spectrum from approximately 720 nanometers to 2500 nanometers. Below the total solar spectrum is illustrated:
Visible light, which accounts for about 44% of solar energy, ranges from approximately 280 nm to 720 nm depending on which scientist you speak to. Before the visible range is UV, Ultraviolet light which accounts for only about 3-4% of solar energy and is almost entirely blocked by either the atmosphere (UVC) or the film (UVA & B).
The remainder of the solar spectrum is the Infrared (IR) which accounts for the remaining 53% of solar energy. Almost all window film manufacturers would be able to claim greater than 90% IR blocking if reporting only one wavelength of the IR spectrum. All three components of solar energy generate heat when allowed to enter your glass. When reporting total solar energy rejected, all aspects of solar energy must be accounted for.
