üleminekuttele

Üleminekuttele is a Finnish term that translates to "transition glasses" or "transition lenses." These are a type of eyeglasses that automatically darken when exposed to ultraviolet (UV) light, such as sunlight, and then return to a clear state when the UV light is removed. This feature allows them to function as both regular eyeglasses and sunglasses, offering convenience for individuals who frequently move between indoor and outdoor environments.

The technology behind üleminekuttele involves photochromic dyes embedded within the lens material. These dyes are reversible molecules that change their structure when exposed to UV radiation, causing them to absorb more visible light and appear darker. When the UV light source is removed, the molecules revert to their original state, and the lenses become clear again. The speed of this transition can vary depending on the specific brand and type of photochromic dye used, as well as ambient temperature.

Üleminekuttele are available in various lens materials and prescription types, including single vision, bifocals, and progressives. They offer a practical solution for people who do not wish to carry multiple pairs of glasses and provide continuous protection from UV rays. While beneficial for many, some users may find that the transition time is not instantaneous or that the lenses do not darken sufficiently in very cold weather or inside a car, where UV-blocking windshields can interfere with the darkening process.