Pinhole Glasses
Pinhole glasses, also called stenopeic glasses are made from an opaque substance that allows many tiny holes in the material through which one can obtain better vision. These glasses are created for people with conditions such as presbyopia, myopia, hyperopia and astigmatism. They are not intended to treat these conditions, only to enhance one’s vision.
The pinholes work by blocking peripheral rays and only allowing rays to pass through the centrally portioned aspect of the pupil. The pupil can be open wide but pinhole glasses will only allow the rays to be passed to that one certain area. As an example of how this works, one can hold a comb in front of their eyes and look through the teeth of it. Essentially, this will give the same effect as pinhole glasses.
While pinhole glasses are a bit on the expensive side, although much cheaper than prescription glasses, they do have several advantages over regular prescription glasses. Unlike prescription glasses that only get weaker over time, pinhole glasses will last a lifetime unless the pinholes happen to break. Scratching of the lens on prescription glases has a great impact on the ability to see clearly; scratches on pinhole glasses does not the alter the ability to see. Pinhole glasses do not need to be cleaned of fingerprints and other smudges as do regular prescription glasses.
People who suffer with cataracts, the passing of light which causes it to scatter, find that pinhole glasses provide a great improvement in their vision. The glasses are also used in the prevention of Myopia, especially in school-aged children who have trouble viewing the board.
Pinholes do have certain limitations and there are some instances where they are not recommended for use.
When using them, there should be an adequate amount of light to focus on the object you are viewing. Also, young people who are very farsighted should not use pinholes.
While pinholes are not intended to treat certain conditions, they are highly effective when used for reading or other up-close work by reducing the amount of focus strain on the eye.
