Photochromic or color-changing, these glasses are transparent in room conditions and become darker when exposed to ultraviolet rays . This way, you do not need second points when you are outside.
How do photochromic lenses work?
Trillions of photochromic molecules in lens change color and structure at high speed when exposed to ultraviolet rays or when the temperature rises. These lenses are transparent indoors and dark outdoors . Some photochromic lenses react to invisible light, for example, sitting in front of a window, the presence of bright sunlight changes color.
Photochromic colors are mainly brown and gray (black).
What are the benefits?
Firstly, photochromic lenses come in a wide variety of materials and designs, with high indices, with one focus, with progressive and bifocal glass.