When I don't have my glasses on, I need to squint to read something, and it seems to help...although only marginally. What are we actually doing when we squint?
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http://www.refractivesource.com/patients/alternatives/nontrad/pinhole_glasses.htm
That will explain it a lot better than I can, but if you dont feel like checking out the link i'll do my best to summarize. When you squint, it allows a smaller amount of light into your retina. The reduced amount of light cuts down on the unfocused rays of light that are processed in your eye, leaving a higher proportion of processed to unprocessed rays.
That will explain it a lot better than I can, but if you dont feel like checking out the link i'll do my best to summarize. When you squint, it allows a smaller amount of light into your retina. The reduced amount of light cuts down on the unfocused rays of light that are processed in your eye, leaving a higher proportion of processed to unprocessed rays.
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Squinting actually changes the shape of the eyeball, thereby allowing (within limits) the light passing through the lens of the eye to fall on the retina (where the visual receptors are located). Near or farsightedness occurs because the images converge in front of the retina or "behind" it. Obviously the image cannot actually focus in front of or behind the retina physically but when the images do strike the retina they are not aligned and are out of focus. Changing the shape of the eyeball literally alters the length of the pass the images travel before reaching the retina, thereby (if you're lucky) enabling the images to converge on the retina and in focus.