Do Contact Lenses Glow Under Black Light?


Do contact lenses glow under black light? Soft contacts don't glow, but hard contact might. (Nieuw)
Do contact lenses glow under black light? Soft contacts don’t glow, but hard contact might. (Nieuw)

Have you ever wondered whether contact lenses glow or fluoresce under a black light? Here’s an interesting question from a reader:

I have a friend who constantly loses a contact lens. I was wondering if I bought him a black light flashlight, if the light would help him find a lens when he loses it? Please let me know if the light would help locate a lens and please advise me where and what type of light I should buy? I thank you for your advice.

If you’re using a black light to make objects glow, you need to make sure it’s a true ultraviolet light, not a black-looking incandescent bulb that just filters all but the (visible) violet end of the spectrum. Most of the inexpensive good black lights use fluorescent bulbs.

Which Contact Lenses Glow Under Black Light?

Soft contact lenses are made from silicone hydrogels. Although some cosmetic contact lenses glow in the dark or under a black light, normal soft contact lenses do not fluoresce when exposed to ultraviolet light. You couldn’t locate a lost lens using a black light. You’d have better luck using a normal flashlight, where the beam might catch the edge of a lens.

Hard contact lenses are made of PMMA (polymethyl methacrylate or Plexiglas). Some forms of PMMA are fluorescent, which may react to ultraviolet light. I’m not sure whether or not hard contact lenses will glow under a black light. If you have a pair of lenses and a black light, give it a try and post a reply.