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 ...

In his famous eye chart, each row represents a different dioptre, which measures the distance you would have to be from the text to read it. Monoyer also inserted his name into the chart.

Eye doctor Herman Snellen (Dutch, 1834–1908) developed the most commonly used eye chart in the 1860s. The now iconic Snellen chart contains 11 rows of capital letters decreasing in size as the eye ...

A perfect 20/20 score on an eye chart test doesn't mean you have perfect vision: Visual acuity, along with color, contrast, and depth perception, are all important parts of healthy eyesight.

The Landolt C eye chart is similar with rows of the letter C, and the tested person indicates in which direction the gap is facing. The Landolt Chart came out in 1888.