Photochromic glasses: how they work in Nigerian sun
Photochromic lenses contain molecules that react to ultraviolet light. Outdoors in daylight they darken like sunglasses, usually within about a minute, and they clear again indoors over a few minutes. They block UVA and UVB with UV400 protection, darken only a little inside cars, and may get slightly less dark on very hot days.
How they work
Photochromic lenses change tint when UV light hits them. More UV means a darker tint. When the UV goes away, the lenses return to clear. You get one pair for indoors and outdoors, with no need to carry separate sunglasses.
In the Nigerian sun
- Bright days: strong sunlight makes them darken quickly and deeply.
- Heat: on very hot afternoons they may not get quite as dark as on a cooler morning. This is normal for photochromic lenses.
- In a car or bus: windscreens block most UV, so they stay fairly light. For driving in bright sun, dedicated sunglasses work better.
- Cloudy days: UV still gets through clouds, so they still darken, just less.
UV400 protection
Our photochromic lenses carry UV400 protection, which blocks UVA and UVB rays whether the lens is clear or dark.
Photochromic or photochromic blue cut?
If you also spend hours on screens, choose photochromic blue cut. It adds a blue light filter for indoor screen use. Plain photochromic lenses start from ₦12,000 and photochromic blue cut from ₦12,000.
Caring for them
- Clean with a microfibre cloth and lens cleaner, not your shirt.
- Keep them in a case, and do not leave them on a hot car dashboard.
- Like all photochromic lenses, the effect can slowly weaken over several years.
Frequently asked questions
How long do photochromic lenses take to darken?
Usually within about a minute in bright daylight. Clearing again indoors takes a few minutes.
Are photochromic lenses good for driving?
They darken only a little behind a windscreen, because the glass blocks most UV. For driving in bright sun, dedicated sunglasses are a better choice.
