Transitions Photochromic Lenses
Photochromic lenses are special lenses that darken when exposed to outdoor sunlight and remain clear when you're indoors. They are considered a jack-of-all-trades since they do the double duty of being used as both a regular pair of eyeglasses and a pair of sunglasses.
Embedded in the lens’ surface are organic molecules that produce a chemical reaction when exposed to UV radiation. This makes the lens tint within 30 seconds. Indoors, with no UV radiation exposure, the lens becomes crystal clear again.
Transition lenses are synonymous with photochromic lenses. The latest generation of Transition lenses (Signature Gen 8) changes quicker than the previous generation. They also darken more and get clearer, and even reduce glare. This means these new lenses can offer excellent UV protection as well as blue light protection. All in all, that makes transition lenses a great value, offering multiple roles in protecting your eyes.
However, there are some things to consider: photochromic lenses don't darken much in the car since windshields filters out natural UV light. This means that, while driving, the lenses might not darken enough for comfort and for good visibility in very sunny conditions. Also, cold weather can slow down the color change, making the transition take longer. And since each brand's photochromic lenses change color at different rates and have different price points, they are not all created equal.
All in all, photochromic lenses are worth the money since they are the Swiss Army knife of lenses with their multiple uses, especially with so many styles, colors, and brands to choose from.