Pinhole glasses do they work?
Pinhole glasses allow anyone with blurry vision to see clearly again without the need for corrective lenses. I first learned of this phenomenon while taking my wife to the eye doctor. They were doing a somewhat standard eye chart test with a simple tool that would block the vision in one of your eyes, thus, allowing your vision in each eye to be tested individually. At the end of the test they flipped a little piece of thin solid black material down to cover the eye. The thing has a number of small holes. Miraculously my wife was able to easily read the line of letters that she has just flunked out on by not getting a single letter correct.
After the doctor left the room, my wife told me about it. So I gave them a try. I was amazed as I mover the pinhole eyeglass thing in front of my eye and back off again, and again, and again!!! I was amazed. The letters from the projector went from fuzzy and unreadable to clear and sharp every time. WOW!!!
You can prove this to yourself right now if you wear glasses by doing this little test using nothing more than your own hand. First, remove any contacts or eyeglasses. Now, simply close one eye and block your vision in the open eye with your fist. Open your fist so that only a very tiny opening is created to look through. Amazingly if you take off your glasses and back away so that you can't read something, and then look again through the small hole of your fist, you will now miraculously bring the letters into sharp detail with that simple little trick. Miracle!
But wait! It gets even better... Maybe, there is lots of anecdotal evidence to show that wearing pinhole eyeglasses can actually improve your vision.
This surely sounds like magic to you, but it is simply a tool that takes advantage of how your eye works. As light enters the eye, the light is focused onto the retina on the back of your eye. This light is first refracted (bent) by the cornea. When you don't need glasses the light is refracted incorrectly so that the rays are focused into a crisp image on the retina.
Most, but not all vision problems occur because the cornea focuses the light either just in front of or just behind the retina. This leads to either nearsightedness or farsightedness. If you have astigmatism the rays of light are focused in more than one place.
OK, so now you know what your eyes are doing, but how in the heck do pinhole glasses fix this problem? Pinhole glasses reduce the effect of the eye's focusing errors by increasing optical depth of field. Put another way. In some people's eyes the light rays entering the eye's lens are not all focused onto the same place on the retina. Rays nearer the center are usually in focus whereas, rays that enter the eye from other points of the cornea are often out of focus. By using a pinhole to see through the out of focus rays get filtered out and you are left with a dimmer but much crisper picture.
So, long story short if you have vision problems you now have a way to correct your vision without prescription eyeglasses. Simply make a pair of glasses or an eye patch out of wood or hide or plastic or whatever you have available and poke or drill a number of small holes in "the lens" and bam! Instant eyeglasses.
