The hidden math behind your DMV’s eye test

At least once in your life, you must have snooped on the eye chart of the doctor's office or the DMV, trying to distinguish the blurred background. The test seems simple enough, right? Read a random sequence of consonants and vowels in a line, then repeat the process with the bottom line until you can no longer distinguish the letters.

It turns out that there are some very precise mathematics that determine the size and disposition of those capital letters to evaluate their ability to see details, what is known as their "visual acuity". It was first developed in 1862 by the Dutch ophthalmologist Herman Snellen, the prototypes of this eye chart began with abstract forms. Finally, the box included those familiar capital letters.

One of Snellen's great achievements was the standardization of the optometric chart so that others could use the same principles to develop their own tests. So we decided to try it. In the previous video, we traced the visual diagram to its origins and closely observed the biology of visual acuity and the mathematics required to test its limits. Then, we reached ridiculous extremes to test my own sight. Spoiler alert: it's amazing.

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