What does an optometrist/optician look at in our eyes when we’re reading from the chart? In what way does that help them?

Question

Coz they still need us to confirm if we can read or not with different lenses.

In: 3

Answer 1

They have the letters calibrated for distance and size in a way that 20-20 vision can reliably read ‘this’ line. So they have you read the best line you can and that corresponds to a certain level of vision and then they use a series of lenses to find the prescription that will get you back to 20-20, or what is considered normal.