

The retina is not as small as a pinhead, but the light from any source doesn’t get focused over the whole thing, it gets focused to a point. Anything else would mean the image is blurred, defeating the point of the glasses.


The retina is not as small as a pinhead, but the light from any source doesn’t get focused over the whole thing, it gets focused to a point. Anything else would mean the image is blurred, defeating the point of the glasses.


Right, but we’re talking about the eye, which glasses are made to focus light into a pin-point with in combination with the natural refractive properties of the eye itself when placed at a specified distance from the eye. Naturally if the glasses were specifically created with a more appropriate focal length, it would be much easier to start a fire with them.


I’m not sure this is correct. Is it not the case that when your glasses are the proper prescription for your eye, the light from any point source is focused onto one place on your retina? Otherwise your vision would be blurred with the image being spread over an area (the normal situation for people with myopia or hyperopia while not wearing their glasses)
But yes, don’t look directly into the sun, with or without glasses.
Most of the mistakes they have to fix are incorrect version numbering.