While you’ve probably never noticed it from the optometrist’s chair, there are only 10 unique letters on that chart–putting you 16 letters short of a usable typeface.

For children 3-5 years old An eye doctor will do a physical exam of your child's eyes, along with vision screenings. They'll use eye chart tests, pictures, letters, or the "tumbling E game." ...

During the visits, doctors of optometry not only check the sharpness of your vision with those familiar eye charts, but they also examine the health of the eyes and eye tissue.

At least once in your life, you must have squinted at the eye chart at the doctor’s office or DMV, trying to make out the blurry bottom line. Turns out, there’s some very precise math that ...