What is that eye test where you look through the eyehole?

ThanksWhat is that eye test where you look through the eyehole?
Well, we do many different tests in an eye exam, and many of them have a little hole you look through. I am not sure which one you are referring to!What is that eye test where you look through the eyehole?
That test is called the pinhole test. Only parallel light rays (focused rays) can go through a pinhole or small aperture. This test gives a good clue as to what your best vision will be. It is also the reason people squint to see better.
be more specific, please. plenty of tests you could be talking about