Total Solar Energy Rejection Vs Infrared Rejection

Most window film companies out there only display the near infrared rays wavelength of 900nm 1100nm giving the misleading data of 99 ir rejection.

Total solar energy rejection vs infrared rejection.

Improperly educated window film dealers crafty marketing on the part of manufactures and a lack of standardized testing can propagate misinformation leading a consumer to conclude that a window film will reject up to 98 of the heat. When the sun is directly overhead all vertical windows with or without film have 100 total solar energy rejection. Total solar energy rejected tser is a factor that describes the total amount of solar energy uv visible ir that is rejected from passing through glass. The infrared portion of solar energy is only one part of the total energy transmitted to earth within the solar spectrum and it does not take into account the significant effects of absorption.

Although it may be natural to consider heat when you think of ir this is not accurate because infrared rays only account for just over half of the total solar energy. Irr measures only the amount of ir infrared component that is rejected by the window film. Two common heat rejection indexes used are irr infrared rejection and tser total solar energy rejection. The total amount of infrared rays rejected by the window film glass.

Furthermore there is no standard method to report these values and most window film product manufacturers unlike vkool report ir rejection. The higher the percentage the higher the percentage of solar energy deflected. Total solar energy rejected tser is the percentage of the total solar energy that is rejected. Most tinting shops use infra red rejection irr as a guide to the level of heat rejection.

However irr does not measure the total amount of heat that is. A lot of people think that infrared ir rejection and total solar energy rejection are the same thing but this is not the case. So if a film has a 65 ir it means the film rejects 65 but lets in 35 ir. Measured over the wavelength from 780nm 2500nm.

Total infrared rejection is a good way to measure the performance differences of like technologies in this case nano particles pinnacle vs stratos to be able to understand the performance improvement between the films. Window films are capable of rejecting infrared ir but oftentimes this can be mistaken for total solar energy rejection. The ir rejection rate is a number that lets customer understand that the film can reject majority of the heat from infrared it does not mean that if a large portion of the ir is blocked.