You've seen it happen—a friend walks inside and their prescription sunglasses magically transform into clear eyeglasses. No, it's not an optical illusion; it's optical science!
Photochromic lenses are eyeglasses that auto-adjust from clear to tinted. But how do these modern marvels shift shades so effortlessly? Let's delve into the light-manipulating alchemy behind photochromic technology.