I went to a doctor for my eye checkup. And I couldn’t read the last line at all. Doctor said this is the limit to your eye and no matter how strong a lens, you would never be able to read the last line

Question

But I don’t get it. Why would if I put a stronger lens, I wouldn’t be able to read the last line? She said you must have never been able to read the last line in your life, and she was correct, but I don’t understand the science at play here

In: 58

Answer 1

There are 2 physical limits to how small you can see:

One is the size of the light sensing cells in our retina. Once details projected on your retina are smaller than this there’s no way to see them.

The other is due to light physically not being able to focus on a perfect point but [a fuzzy disc](https://en.wikipedia.org/wiki/Airy_disk). Anything smaller than this will be blurred out by the light itself.

So even with perfect glasses and a perfect lens in your eye there are always limits to what you can see unless you magnify the image with a telescope/binoculars.