When we think about the choice of sunglasses, it is good to bear in mind the conditions in which we will use these glasses. Each condition has a different intensity of sunlight, as well as different types of lenses with a given light transmission. This light transmittance is given as the amount of light, expressed as a percentage, that it is able to penetrate the lens. The higher the percentage, the more light the lens passes through and the other way around. The lens with a transmittance of over 90% is therefore suitable for worse lighting conditions such as cloudy, overcast or snowy. On the contrary, we choose a lens with a lower percentage of transmittance for conditions where we have to protect our eyes even more from the sunbeams.
|CATEGORY||VISIBLE LIGHT TRANSMISSION (VLT)||USAGE|
|Cat 0||80 – 100 %||Indoor and cloudy weather|
|Cat 1||43 – 80 %||Low brightness|
|Cat 2||18 – 43 %||Medium brightness|
|Cat 3||8 – 18 %||Bright light, water & snow|
|Cat 4||3 – 8 %||Extreme bright light (glacier or desert)|