No need to carry two spectacles in your pocket when you move between indoors and outdoors. The Varitint Spectacle will change for you. Varitint Lens is available with a series of attractive frame colors. Meets ANSI Z87.1 standard. The time to shift is not constant nor is it instantaneous.
All photochromic lenses require UV Light exposure to function.
Time, temperature and season also have an effect upon the ability of the lens to shift color. The stronger the sunlight, the more active the shift of the lens. The Varitint Lens, as with all ophthalmic photochromic lenses, will not work inside a car, because glass windows block UV light, effecting the ability of the lens to shift. The Varitint Lens will begin to shift back to clear when removed from UV light exposure. Paramount Corp. All rights reserved worldwide.