Normally, your pupil gets smaller when light shines into it. In dilation, your doctor uses special eye drops to force the pupil to stay open. This allows them to see much more of the back of your eye, including the entire retina, the part of the retina called the macula, and the optic nerve.

Is eye Dilation painful?

A dilated eye exam involves widening, or dilating, the pupil so the eye doctor can get a better view into your eye. The doctor dilates the eye using special eye drops. It's not a painful process, and is tolerated well by most people.

How do your eyes become dilated?

Muscles in the colored part of your eye, called the iris, control your pupil size. Your pupils get bigger or smaller, depending on the amount of light around you. In low light, your pupils open up, or dilate, to let in more light. When it's bright, they get smaller, or constrict, to let in less light.