Pinhole glasses, as the name implies, are glasses with tiny holes poked through their lenses. Whereas contact lenses and standard glasses redirect and focus rays of light into the retina, pinhole glasses are actually intended to limit the amount of light that can get in. This can be helpful in certain clinical settings, especially for people with myopia or astigmatism.
Eye doctors use pinhole glasses as a diagnostic tool. When someone has an eye condition, refocusing and limiting rays of light with pinhole glasses is a way to narrow down what the cause could be. There are also limited and ongoing studies about their therapeutic uses, particularly for presbyopia.
Do Pinhole Glasses Really Improve Your Vision?
The shortest answer would be, “No.”
According to the American Optometric Association, 30% of Americans live with some form of myopia. With numbers like that, it’s easy to see why so many search for miracle eyesight fixes and why stories about pinhole glasses abound.
Many people first hear about pinhole glasses through alternative channels that advertise them as a treatment for myopia, astigmatism, and other eye conditions. Though it’s a popular claim, there’s very little evidence to support it, and the U.S. Federal Trade Commission barred U.S. companies from advertising pinhole glasses in this way back in 1993.
The fact is that someone with myopia or astigmatism who wears pinhole glasses will see more clearly as long as they’re wearing the glasses, but the effect goes away after they’re removed. You can achieve a similar effect by squinting.
Since they block peripheral vision, pinhole glasses are completely impractical for use outside of controlled settings, and they should certainly never be worn while doing something as important as driving. Moreover, clinical studies of people using pinhole glasses for reading found that they experienced excessive eye strain while doing so.
Testing the Claims About Pinhole Glasses
Researchers interested in investigating the claims about pinhole glasses assembled a test group of 36 participants and had them test their vision using the much advertised multiple-pinhole (MPH) and single-pinhole (SPH) glasses. The aim of the study was to test the effect of pinhole glasses on factors like:
- Visual acuity
- Pupil size
- Depth of focus
- Visual field
- Reading speed
- Ocular discomfort
They found that both sets of glasses actually provided temporary improvements in near and distant vision, but at the expense of most of the other tested factors. People using the MPH glasses could see the text more clearly and read it faster than those using SPH glasses, but they also experienced a lot more eye strain and discomfort in the process.
Clinical Uses of Pinhole Glasses
Pinhole glasses are useful for eye doctors who want to pin down the source of an eye problem. They’re often used alongside an occluder, which is the instrument eye doctors use to cover your eyes as you read an eye chart.
The purpose of pinhole glasses is to reduce the amount of light your eye has to cope with. If pinhole glasses temporarily relieve the pain you’re feeling in one or both of your eyes, that could provide the doctor with an important clue about what’s causing the condition in the first place. Seeing the same with or without pinhole glasses could be a sign of amblyopia, or lazy eye.
Similarly, pinhole glasses are a helpful way of identifying myopia in adults and older children. When someone complaining about their vision sees more clearly using pinhole glasses, this is an important sign of myopia. If their vision actually gets worse while using the glasses, however, that could mean they could have macular disease or opacities in the central lens.
Pinhole glasses as a possible presbyopia aid:
Presbyopia is a condition where your short-range vision gradually gets worse, even while your vision at other distances stays the same. It often occurs naturally as you age. Presbyopia’s symptoms include:
- Headaches while doing close work like writing
- Blurry vision while reading text
- Feeling like you need to hold books at arm’s length to read them clearly
Some eye doctors working with presbyopia have cautiously reported success using pinhole glasses. Namely, the glasses allowed people to read text more clearly for brief periods of time. This came at the expense of slow reading speed and eye fatigue, however. The doctors concluded that pinhole glasses have pros and cons that should be weighed carefully.
Alternatives to Pinhole Glasses for Vision Improvement
The lack of scientific evidence for pinhole glasses as a way to improve vision means that they’re probably best left in the hands of eye doctors. Nearsightedness, astigmatism, and other conditions can be treated with customized glasses and contact lenses. In addition, laser eye surgery (LASIK) has grown into a popular, semi-permanent fix for various eye problems, though it may not be appropriate for everyone.