Pinhole Glasses Provide Focused Vision

By Author: Mike Lamb
Total Articles: 62
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People need glasses because their eyes are chronically out of focus. In case of myopia, the light rays come to focus in front of the retina and in case of hypermetropia, the light rays come to focus behind the retina. This leads to a blurred effect.

When normal prescription glasses are used to rectify this defect, the ciliary muscles in the eye begin to lose strength. As a result stronger and stronger glasses are required for clear vision. The reason behind this is, normal glasses assume a constant "refractive error", a degree which represents either short-sightedness or long-sightedness. We are able to see clearly through these glasses because we continuously produce the refractive error that the glass was designed for. People with normal vision will not be able to see clearly with these glasses because they don't produce this refractive error. This is not a good option as you have to visit a doctor for new glasses every time your eye demands for stronger power.

There is an alternative to this--the pinhole glasses. Pinhole glasses ...
... are actually not made of glass. It is made of any opaque substance. For example, either metal or plastic. These glasses have a series of perforations on the substance present in the place of lenses. The user can see through any of these pin holes. These glasses are also called as "stenopeic glasses" (stenopeic is the Greek word for pin holes).

Normal glasses do not reduce the width of the bundle of diverging rays coming from different parts of the object. These peripheral rays are the ones which make up the "blur circle". Pinhole eyeglasses have the advantage of reducing this width. By blocking these peripheral rays, pinhole eye glasses allow only the rays which pass through the center of the pupil. By cutting the other rays the blur effect is reduced substantially. Even though the pupil is wide open only the central portion is receiving the light. When compared to normal prescription glasses, in case of pinhole glasses, the vision improves because the eye muscles develop. Moreover pinhole glasses provide a focused vision. Thus, you need not produce that so called "refractive error" to view the objects clearly. As a result you eyes are not going to demand for stronger power. By performing some exercises while using pinhole glasses, there can be a permanent remedy for the defect in the eye. Apart from these, pinhole glasses can also be used by people with cataract, as sunglasses and also as computer glasses.


Mike has been writing and publishing articles about health products. He recently came across a website on pinhole glasses which gave information about this old technique of using pinhole glasses for eyesight correction. Here's an article about pinhole glasses.