Viewing The World Through Two-Colored Glasses

April 3, 2010 10:38 AM

Any harm in wearing sunglasses with two mismatched lenses?

To make a long story short, I own a pair of sunglasses with removable lenses. I scratched one lens badly, and bought a replacement set. Then I scratched a lens in the replacement set. I then noticed that, between the two sets, I had one clean pair of lenses. Later, after wearing them a while, I noticed that one of the lenses is grey and the other is amber. I haven't noticed any adverse effects after a few months, but I can't help but wondering if doing so will eventually cause some sort of trouble for my eyes. I wear these shades constantly, as direct sunlight gives me headaches.

A few possibly relevant details: Neither lens is polarized, they're both polycarbonate, and they're wraparounds. Also, when I close one eye to look through each lens, I don't really see a difference. But when I hold the glasses out and look at them, one lens is clearly different from the other.

So, any harm in wearing my slightly mismatched shades?

posted by Doctor Suarez to health & fitness (5 answers total)

nah, your eyes will adapt. you may get weird looks from other people though. this is why i buy $10 mall kiosk sunglasses.
posted by Mach5 at 11:35 AM on April 3, 2010

Now you will be able to see everything in 3D!
posted by Some1 at 12:00 PM on April 3, 2010 [3 favorites]

Sounds like a recipe for headaches to me. But go ahead. I'm curious.
posted by swimming naked when the tide goes out at 1:56 PM on April 3, 2010

Now you will be able to see everything in 3D!

Whether you want to or not. Maybe.

There is something called the Pulfrich effect that depends on mismatched lenses of a certain kind (one darker than the other) that produces a perception of depth where none exists, basically because the eye with the darker lens sends its information to the brain on just a little bit of a delay (the reason tennis matches are called on account of dimness), making any object in motion look as if it's in two places at once. This is just how binocular vision works, however, with an object appearing to be in one place with one eye and another with the other, so the brain fuses the image and the delayed image and gives a sensation of depth.

The overall difference in brightness between your lenses may not be great enough for you to see depth that isn't there in every moving object you look at, but the difference in colors of the lenses has a better chance of resulting in brightness differences at those colors sufficient to displace objects of those colors, or it could possibly make objects with components of those colors appear blurrier.
posted by jamjam at 5:19 PM on April 3, 2010

I had a pair of sunglasses that lost a lens, and out of bored curiosity I wore them around for a few hours, until I developed a rather notable headache. Granted, that's anecdotal and probably a more extreme case of brightness difference than what you're dealing with, so YMMV.
posted by FatherDagon at 2:51 PM on April 5, 2010