
Contact lenses are used to correct vision disorders, treat corneal conditions, and change eye color. The appropriate lens type, diameter, base curve, and prescription are determined through an examination by an eye doctor.
A well-fitted contact lens should be properly centered on the eye, have a good corneal coverage, not exert pressure on the edge, provide clear and comfortable vision without being felt by the wearer, maintain consistent vision after blinking, and have slight movement to allow tear circulation.