Qualifications
It helps to be meticulous, have a keen eye for detail, and have great hand-eye coordination.
You also have to be really, really good at science-ing. And math-ing.
And you've got quite a bit of schooling to get through.
You'll have to get your bachelor's degree (that's four years); take the MCATS, get a high score and go to Med School (another four years). Then you'll have to become an intern and a resident, specializing in ocular medicine, possibly with a sub-specialty like glaucoma or corneal transplants (three to five years). You must also take a difficult two-part test by the American Board of Ophthalmology to become Board Certified (source).
It could be fifteen years of schooling, so strap in and hold on tight.