What Are Photochromic Lenses?Updated a day ago
Photochromic lenses are lenses that automatically darken when exposed to UV light and return to clear (or a much lighter tint) once that UV exposure goes away. Instead of choosing between a clear lens and a tinted one, a photochromic lens adjusts on its own as the light around you changes.
The Short Answer
Photochromic lenses contain light-reactive molecules built directly into the lens material. When those molecules are hit with UV light, they change structure and begin absorbing more visible light — which is what makes the lens look darker. Once UV exposure drops off, the molecules gradually shift back, and the lens lightens again.
The amount of UV light determines how dark the lens gets. Bright, direct sun triggers a stronger reaction and a darker tint; lower UV conditions trigger a lighter one.
Revant Photochromic Lenses
We offer photochromic lenses in three colors, all non-polarized, with a VLT (Visible Light Transmission) range of 16-88%. That range reflects how much the lens shifts — from a light, nearly clear state indoors or in low UV, down to a much darker tint in full sun.
- Stealth Black Photochromic
- Gray Green Photochromic
- Coastal Blue Photochromic
Each color transitions through its own shade as it darkens, but all three share the same 16-88% VLT range and the same non-polarized construction.
Important: These Only Transition in Full UV Light
Photochromic lenses respond specifically to UV light — not just visible brightness. That has a few practical effects worth knowing before you buy:
- They will not darken behind car windshields. Windshield glass blocks most UV light, so photochromic lenses generally stay clear or lightly tinted while driving.
- They will not darken indoors, even near a sunny window. Regular window glass filters out UV light the same way windshields do.
- They need direct, full sunlight to fully transition. Overcast days or shaded areas will produce a lighter tint than direct sun, since there's less UV to react to.
How Long Does It Take to Transition?
Photochromic lenses don't change instantly. Expect the lens to noticeably darken within the first minute of direct sun exposure, with the transition continuing to deepen over the next few minutes until it reaches its full tint. Clearing back up when you head indoors follows the same gradual pattern, typically taking a few minutes to fully lighten.
Find Your Fit
Not sure if photochromic is the right fit for how you use your sunglasses — versus a gradient or standard tint? Our Eyewear Experts are glad to help — reach out any time and we'll help you find the right lens for your lifestyle.