Posted on Apr 15, 2014

How is it different than more conventional solar film? How is a film classified as being spectrally selective?

Good questions considering that the term has been used in regards to solar solar film in recent years. These films have been engineered to allow the maximum transmission of visible light while rejecting the maximum amount of UV and Infra Red wavelengths. Spectrally selective films are different from the more conventional solar films in that the chemistry that is rejecting solar energy does not use shading or reflectivity that is visible to our eyes. This results in a product that begins by not impeding our view of the beautiful landscape we have invested in heavily and finishes at improving our visibility of the landscape by reducing glare. Some interpretation of this may vary, but technically speaking a film is commonly classified as a being spectrally selective if the ratio of its VLT divided by its SHGC is greater than 1.

A couple of examples of these are:

  • Purelite 60; VLT is 60% and its SGHC is 0.57 = 0.60/0.57 for 1.05
  • Huper Optik Sech; VLT is 60% and its SHGC is 0.46 = 0.60/0.46 for 1.3