Sunglasses For Men Photochromic Reading Transition Glasses Hyperopia Presbyopia with diopters

Brand Name: EOOUOOEGender: Men, UnisexLenses Color: ClearEyewear Type: Reading GlassesLenses Optical Attribute: PhotochromicCoating: HMCLenses Material: CR-39Item Type: EyewearFrame Material: AcetateModel Number: 6541Lens Width: 4.9inchLens Height: 4.1inchItem Type: EyewearEyewear Type: Reading Glasses Sunglasses For Men Photochromic Reading Transition Glasses Hyperopia Presbyopia with diopters 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. Frame Length Lens Length Lens Hength Beams Length Arm Length 135mm 49mm 40 mm 20 mm 138mm Brand : CHASHMA CHASHMA Size: 49-20-138 Eyewear style : Eyewear Model : 21018 Frame Material : Alloy Eyewear Type: Reading Glasses Gender : Men Characteristics： Photochromism Frame Type : Full rim Lens Material： HD Resin Gun gray Brown