How do transition sunglasses work?

Question

My friend has transition glasses, all I know about them is they transition to dark in the sun. but how do they work? can someone please explain like im 5 years old?

In: 69

Answer 1

Silver compounds in the lenses react to sunlight and darken the lens. When the sunlight is removed (by going back inside) the chemical reaction reverses itself and the lenses become less dark