Pinhole Glasses: The Basics

By Author: Mike Lamb
Total Articles: 62
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How They Work

Pinhole eyeglasses contain a series of perforations, or pinholes, through an opaque plastic sheet set within each lens.

In order to focus on objects at various distances -- close-range, mid-range, and long-range -- the eye's lens must rapidly change shape. This capacity is called "accommodation." However, accommodation often diminishes with age to the point of interfering with one's ordinary range of visual activity.

Looking through the pinholes reduces the pupil's aperture, thus narrowing the beam of light passing through the eye's lens. This produces a greater depth of field.

Since a narrower beam of light casts a smaller, less blurry circle on the retina, vision improves. Users report better brightness, sharpness, and clarity.


How They Help

Pinhole eyeglasses can help correct for a loss of accommodation, particularly when focusing mid-range ...
... to long-range. Also, they work best in well-lighted settings. This makes them useful, for instance, in classroom settings (such as reading words on a blackboard or whiteboard), or when viewing sources such as an overhead projector, TV screen, or airport monitor.

Also, they are also much less expensive than standard eyeglasses, and can be obtained without an appointment or prescription. (In fact, during eye exams, ophthalmologists often scan for refractive disorders using pinhole-based equipment.)

Used properly, then, pinhole glasses can provide a more affordable and convenient alternative to standard eyeglasses.


Advice for Safer Use

Since pinhole glasses do nothing per se to protect or augment vision, please use common sense when wearing them. If you use pinhole eyeglasses as a reading aid for print, it is still important to have a good reading lamp on. If you use them at the computer, it is still important to view your monitor at a comfortable distance (a bit over two feet from your eyes), and to rest your eyes at least hourly. Since pinholes restrict peripheral vision, do not use them while in motion, such as while driving. Nor do they protect against solar UV rays, so please do not wear them as sunglasses.

Even then, pinhole glasses are not for everyone. For example, they may not help those with over six diopters of near-sightedness, due to the increased range of diffraction, or the spreading of light, which causes multiple focal points as light passes through the eye's lens. Nor are they helpful for young, near-sighted people, who need to strengthen their eye muscles unaided.


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.