Visible light transmission (VLT) refers to the amount of visible light that passes through a goggle lens. It is expressed as a percentage of the total amount of light that is incident on the lens.
The visible light transmission of ski goggles is an important factor in determining the amount of light that reaches the skier's eyes, which affects their visibility and comfort on the slopes. A higher visible light transmission results in clearer, brighter vision, while a lower visible light transmission helps reduce glare and improve contrast.