A Beam of Light Through a Pinhole
When we were children, a beam of light through a pinhole on to a sheet of paper was how we watched an eclipse. It was the only safe way to view an eclipse of the sun. We clearly understood warnings that looking directly at the sun during an eclipse could send us blind.
The concentrated beam of light would cause lifetime damage to our vision, by actually burning the image into our retina. If that sounds a little scary, think of how you can burn a piece of paper, with a magnifying glass.
It’s natural to blink when looking at the sun, and during an eclipse, you are much less likely to blink. Instead, you stare.
A Failing Beam of Light – 2004
Even if we followed all those rules, we regard failing vision as one of those unavoidable symptoms of getting older. Â [Read more…] about A Beam of Light Through a Pinhole