Pinhole Glasses - Further Reading

Extract from p206. Natural Vision Improvement.

Pinhole spectacles are not glasses at all, nor is the idea of reducing light anything new. Eskimos in 'white out' snow conditions used to carve goggles of wood with a narrow horizontal slit across the front. This allowed them to travel in an environment where light was coming from every direction and all contours were missing. If that Eskimo had been myopic (not many Eskimos were, until they started going to school), she/ he might also have seen more clearly. The clarity given by the pinholes is due to the fact that the blur circle on the retina is reduced.

This figure depicts what occurs when pinhole spectacles are placed in front of a myopic eye looking at a distant object:

1. Parallel light entering this (short-sighted) eye is brought to a focus within the eye ( F) and produces a large blur circle on the retina.

2. The moment a pinhole is introduced in front of the eye a much narrower parallel pencil of light comes through the hole. The light again goes through the focal point F resulting in a much smaller blur circle on the macular area.

People with both close and distant blur, and astigmatism, are able to use pinhole spectacles as T-glasses while they're in the process of improving their sight through natural means. Pinholes have some disadvantages. They are not useful at night nor recommended for driving. They reduce peripheral vision and most driving laws require compensatory lenses.

One of their greatest advantages is that they are not prescriptive. Almost everyone, no matter what their error of refraction, sees clearly through the holes. In addition, they encourage saccadic motion. Staring through them is unusually counterproductive. Using the pinholes temporarily for reading, viewing, and theatre going is very handy. They are inexpensive in comparison to prescriptive glasses.

It is important if you do obtain pinholes to use as T-glasses that you give yourself some time to adjust to them. They have a honeycomb effect that is distracting at first if the eyes are extremely decentralized (see chapter 11). Put them on, do some yawning, edging from Chapter 6, and blinking until your brain says. 'This super clear vision is all right'. At this point the brain stops paying attention to the black occluding plastic and tunes into the messages coming through the pinholes.

An ophthalmologist recommends using the pinhole effect - 'when you lose your eyeglasses in the woods, try viewing through the pinhole. Vision will be improved. Pinhole glasses would be used more frequently except that they decrease the illumination and the field of vision.' (Steven Goldberg, M.D.:: Ophthalmology Made Ridiculously Simple, p.12) Perhaps Dr Goldberg does not realize there may be a more intriguing reason why pinholes are not used more. They have in fact been harshly suppressed by legal means in several countries. Thanks to the persistence of an Australian woman living in California, who spent $70,000 in legal fees to keep her product available through health food stores, the pinholes can be obtained.