Ok, that title might be a bit misleading. It should probably say something along the lines of how to improve your sight if you wear glasses or contacts. That’s a bit of a mouthful though.
Minute Physics show us by exploiting some simple physics (that you’ve probably seen in use on cameras without really realising it) you can make text or objects clearer.
Make a tiny hole with your finger (curling up your index finger works best) and look through it. You might feel a bit silly doing it, but try it. It works! Incredible!
Granted it’s not a viable alternative to using contact lenses or glasses, but it might save you some bother if you don’t have them to hand and you need to view something in a little more focus.