If you need corrective lenses, you’ll get a refractive assessment, a test that determines how light waves bend. The results of these tests help the doctor determine your prescription. He may put a Phoroptor, a device that resembles a big black mask, over your eyes in order to fine-tune these measurements. Your peripheral vision will also be tested. A slit lamp exam uses a microscope that emits a sharp beam of light to evaluate the cornea, lens and iris. The back of the eye is also examined and finally your eyes will be tested for glaucoma.