Pinhole glasses

August 25th, 2009

Pinhole glasses or stenopeic glasses utilize opaque materials with small perforations in each lens, rather than glass lenses, to reduce blurriness for people with vision problems. The perforations reduce the amount of diverging rays that hit the pupil from a viewed object, thus reduced blurriness in people with refractive vision disorders. Refractive vision disorders include myopia, presbyopia, and farsightedness. There are also benefits for people with cataracts, a cataract is an opaque spot on the eye that causes light to scatter when entering the pupil, the use of pinhole glasses, reduces the amount of light hitting the cataract, less light is then scattered, and as a result blurred vision can be improved dramatically.

There are many advantages in choosing pinhole glasses over prescription glasses. The first is cost, prescription glasses are expensive and their use of glass lenses leaves them vulnerable to scratches and glass lenses break if dropped. The glass lenses in prescription glasses also need to be cleaned of fingerprints and debris, to maintain clear vision through the lens.

It is believed that the eye disorder myopia can be prevented, by using perforated lenses. Myopia is caused when the eye extends to due excessive close work, when a person develops Myopia, light entering the eye focuses before the cornea. This results in extremely blurry vision, reducing the amount of light entering the eye, eases eye strain when performing work in close proximity to the eyes.

There are certain disadvantages to using pinhole glasses. Their perforated opaque lenses reduce the wearer’s peripheral vision, which can be dangerous in certain situations. They should not be worn while driving, operating heavy machinery, or when safety glasses are required. It is also a good idea to avoid wearing them in dim light situations, as the perforations reduce the amount of light entering the eye. If using them as reading glasses, extra light will be needed to reduce eyestrain.