Visible Light Transmission (VLT) refers to the percentage of visible light that passes through the lens of laser safety glasses. This value affects how bright or dark the eyewear appears when worn.

A higher VLT allows more visible light to pass through the lens, providing brighter vision. Lower VLT values create darker lenses that reduce brightness.

Balancing VLT with laser protection is important. While high optical density filters provide strong laser attenuation, they may also reduce visible light transmission.

In many professional environments, eyewear must provide adequate laser protection while still allowing operators to clearly observe equipment, workpieces, or treatment areas.

Lens specifications typically include the VLT percentage so users can evaluate how bright the lens will appear.

Understanding visible light transmission helps users select protective eyewear that maintains both safety and practical visibility.