The pros and cons of glasses how to identify color lenses?

1. High quality color lens surface, free from scratches, bruises, wool surface, pitting, welcomed optical lens oblique observation, degree of finish is extremely high. Inside the lens no spots, stones, stripes, bubble, crack, pervious to light and bright. 2. Two pieces of color glasses lens, lens must be the same quality and no difference color wants even, can't present several kinds of color, no 'color' of Yin and Yang; See the sunshine, color changing fast, no sunshine, the fading time faster. Inferior slow lens discoloration, fading fast, or become angry fast, slow fading. Poor color glasses does not change color. 3. BianSeJing two pieces of lens thickness should be consistent, not a thick, thin, otherwise, can affect vision, impair the health of the eyes. Single chip thickness is even, if it is color flat lenses, the thickness of about 2 mm advisable, smooth edges. 4. Without any feeling when wearing, not giddy eye bilges, observe objects is fuzzy, not out of shape. When buying, take glasses, monocular through the lens, see distant objects, move up and down the lens, distant objects move should not happen illusion. 5. Discoloration speed: high-quality BianSeJing, have rapid response ability to environment, put under sunlight BianSeJing about 10 minutes, which should reach big color depth, or discoloration of poor quality. Will have under the fluorescent color glasses to the dark, lens surgery for high-quality BianSeJing time no more than 20 minutes. 6. Protective: high-quality BianSeJing, can block 100% uv ultraviolet B, provide Dai Jingzhe effective uv protection.
related: glasses color glass lens