Pure Titanium Photochromic Myopia Glasses Men Watertight Ultralight Reading Optical Glasses Women Sun Automatic Discolorat -175
Tips: This is a finished myopia glasses, and there is no astigmatism. It is not reading glasses,

please confirm before buying. "-" means glasses for myopia, "+" means reading glasses,

What are photochromic lenses?

Photochromic lenses are also referred to as light-sensitive lenses". Glass lenses are adding silver halide, but now is the mainstream of photochromic resin lenses, adding of spiro and other chemicals in the acrylic resin lens, so that the original colorless and transparent lenses, in bright light, will become colored lenses, to do the protection, so is suitable for indoor and outdoor use.
Photochromic lens optical glass containing silver halide microcrystals, phototropy reversible reaction according to the principle, in the sunlight and UV irradiation variable dark, completely absorb ultraviolet and visible light absorption of neutral; back to the dark, can restore the colorless transparent.
Photochromic lenses are mainly used in open-air fields, snow fields and indoor light sources, so as to prevent sunlight and ultraviolet light from damaging the eyes.
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