How do photochromic lens glasses change color under the sun?
So, how do color-changing glasses achieve color change when exposed to light?
Well, the lens of the color-changing glasses is made of a material called "photochromic glass". Since the invention of this kind of glass lens in 1964, glasses with this kind of lens have been popular with customers. In that way, this kind of magical glasses is How to change color when seeing sun light?
Color-changing glasses can change color by light because the lens of this kind of glasses contains silver halide (silver chloride, silver bromide) microcrystals. When it is irradiated by ultraviolet or short wave of visible light, the halogen releases electrons and the electrons are captured by silver ions. Silver ions will be reduced to silver atoms, and silver atoms will absorb light, the transmittance of the lens will decrease, and the color of the lens will become darker; when the light becomes darker, the halogen in the lens will react reversibly, and the silver and halogen will react at this time. Combined, the lens will return to a transparent or light-colored state.
So, how should we choose when buying color-changing glasses? First of all, the color of the lens and the depth of the lens color should be determined according to personal needs, but it should be noted that the color of the two lenses of the color-changing glasses should be the same with no significant difference in color depth. High-quality color-changing glasses will change color fast after seeing the sun, what’s more, the color fades quickly too after the light is dark. But poor-quality photochromic lens glasses may change color slowly, fade slowly, or do not change color at all.
So use sun light to test, then you can know how to option. :)
