eli5:How do colored contacts work when your pupil widens/narrows? do they move along with the pupil, or do you see the contact on your eye when your pupils dilate, or something else?

Question

eli5:How do colored contacts work when your pupil widens/narrows? do they move along with the pupil, or do you see the contact on your eye when your pupils dilate, or something else?

In: 5

Answer 1

Optometrist here: Most of the newer colored contacts have an opaque color that has a pupil opening about the size of an “average” pupil in normal room lighting. It doesn’t change. If you go into a dark room or if your pupil is larger than normal, you are likely to see the edge of the “pupil” in the contact, but most of my patients either don’t notice it or just don’t say anything. I can’t think of a single patient that has complained about it being something that has bothered them.

But to answer your question directly, the pupil size in the contact does not change. It’s constant and is “printed” on the lens.