Glossary

General information about sun radiation:
Sun’s radiation comprises of 3 components, being the infrared, visible light and ultraviolet rays. Infrared (IR) gives the warm heat feel; visible light (VL) enables visibility; and ultraviolet (UV) causes materials fading and skin cancer.

Definitions of film specifications:
VLT: Visible Light Transmission
Visible light transmission measures the amount of light that passes through a glazing system. A high VLT means more light is enter, giving clearer view in and out.

VLR: Visible Light Reflectance
Visible light reflectance refers to the amount of light being reflected by a glazing system. A mirror effect is resulted when high visible light is reflect. Hence, the higher the VLR, the more a piece of film will resemble a mirror.

Glare Reduction
Glare reduction measures the percentage of reduction in visible light transmission through a glazing system without film to that with film.

IRR: Infrared Rejection
Infrared (IR) is the major part of solar radiation that contributes to heat. IR is absorbed by the interior materials and skin, making them warmer. The higher the IRR, the more heat is rejected. You may also find the term spectrally selective being referred to as a film with high VLT and high IRR.

UVR: Ultraviolet Rejection
Ultraviolet rejection measures the percent of total ultraviolet ray rejected from passing through a glazing system. Most of the window films are able to perform this benefits.

TSER: Total Solar Energy Rejection
Total Solar Energy Rejection (TSER) is the combined energy rejection of the visible light, infrared and ultraviolet. A high TSER reading does not necessarily mean a high heat rejection as it could also mean a high visible light rejection. Therefore, given the same infrared rejection capability, a darker film gives a better TSER reading than that of a lighter film. To ensure that a film has a good heat rejection performance, it is best to look at the infrared rejection specification.

SC: Shading Coefficient
Shading coefficient measures the solar energy transferred through the glass compared to the energy transferred through 3mm clear glass. The lower the shading coefficient number, the better the solar shading qualities of the glazing system.

Film Thickness
The thickness of the film is often given in mils. 1 mil is equivalent to 0.001 inch. A thicker film is usually stronger than a thinner one.

Tensile Strength
Tensile strength measures the force required to break an area of 1 square inch film.

Peel Strength
Peel strength measures the adhesion strength of the film (in pounds per inch). A high peel strength indicates a stronger bond between the glass and the film.