Photochromatic sunglasses
The same pair of glasses for everything!
Photochromatic lenses are clear indoors and darken once they are exposed to UV light outside. With these glasses you will have the advantage of not having to switch between different sunglasses. Sunglasses with photochromatic lenses are especially useful for people who have to continuously move between lighter and darker areas, such as cyclists or people who are sensitive to light. The way it works is by trillions of photochromatic molecules quickly changing in colour, size and structure when exposed to UV light or when temperature increases, causing the lenses to darken.