Speccy Four Eyes

There’s no two ways about it, glasses are cool these days, with celebs across the globe putting on a pair when they want to make a statement or (whisper it) look a bit smarter. There are even awards for Glasses Wearer Of The Year celebrating the humble things people put on their faces so that they can see.

The lenses in glasses work use the same principles of light refraction I’ve previously mentioned, and it’s the specific shapes that the optician makes that means that the wearer can see more clearly.

Lenses come in two basic shapes, concave and convex. Concave lenses are for people with short sight and convex for people with long sight. Convex lenses are also used in binoculars and other tools that need lenses for seeing long distances.

The shapes of the lenses changes where the beams of light all focus, which is called the focal point. You can see this has the effect of moving the focal point around the eye, which is how the vision becomes clearer

All these huge frames and bright bits of plastic though, that’s fashion and has nothing to do with Physics!