When I squint my eyes, my vision gets a little be clearer?

Why is this? I have really bad astigmatism and have been wearing glasses since I was 5. I've always wondered why this happens.When I squint my eyes, my vision gets a little be clearer?
What you are talking about is related to what is called depth of focus. If you have ever taken pictures with the old non digital 35mm SLR cameras, this is exactly the same. If you want to take a picture of a person about 5 feet away and also want the mountain top (miles away) to be in focus then you make the aperature of the camera very small. The small aperature extends the depth of focus of the lens so that both the person and the mountain APPEAR to be in focus. The mountain top is not actually focused upon by the lens BUT because the mountain falls within the depth of focus then it APPEARS to be in focus. Now, if for effect, you want the person to be clear but the mountain top to be blurry you would make the aperature very large. This will compress the depth of focus range so that the mountain top is not only out of focus but it also APPEARS to be blurry because it is outside the depth of focus range for the lens.





Now lets apply this to your situation. If your glasses were exactly the power they should be then what you are looking at will be in focus. BUT if you are having to squint to see clearly, than what is happening is that the size of your pupil is large enough that the depth of focus of your eye does not extend to the object that is blurry. By squinting your eyes, though, your are artificcially creating a smaller pupil (aperature) so as to extend your depth of focus to include the object which you are wanting to see more clearly. There ya go. Hope this helped.When I squint my eyes, my vision gets a little be clearer?
I had this question too!! It's because your eye lashes act are so fine that they act as a lens (if that makes sense). Hope that helps! Cuz it doesn't sound like it even makes sense. but it's true... :)
When you squint, you make the opening the light passes through smaller. This means that less of your lens is exposed, and there is less opportunity for individual rays to go astray, so you see more clearly. I'm nearsighted, and way back before I got glasses (when I was around 8 or so), I used to do essentially the same thing by curling my index finger and thumb to make a small pinhole, and looking through it.
';the pinhole effect';. eliminating ';paraxial'; or off-axis rays.





its the optical phenomenon thats the basis for pinhole glasses...
that's y u need to wear glasses constantly