Sunglasses to choose 'eight note'
the first first to see if the lens is a scratch, bubble, impurities, stripes, check the packing for sunglasses, regular sunglasses should be marked with name, color, diameter, quality levels, production factory name and trademark, the mirror or tags are marked as both UVA and UVB rays and CE mark sunglasses can ensure that block uv.
the second sunglasses to wear when the choose and buy did try the feeling of dizziness, headache. Now there are some marked degree of myopia sunglasses for sale, but because of pd and other indicators vary from person to person, so if there is no guidance of professional personage, consumer is good not to choose this prescription sunglasses.
the third sunglasses with your hands two horns on the fluorescent lamp, mirror reflective article gently rolling, if it is found that mirror the daylight lamp shades appear wavy, twisted, prove that the lens is not flat, the mirror can damage eyesight.
the fourth lens to level off, the definition is higher, the sun lens material has two kinds of glass and resin, and a good sun lens polarized lens should be used. It USES as well as contact lenses and precision made of synthetic resin, synthesized from 7 layer chip, two outside layer is hard wear-resisting layer; Layer 2 and layer is 6 shatter-proof strengthening layer; Layer 3, 5 is uv filter layer, middle layer is polarized filter layer. Polarized lens can effectively filter out reflected light and harmful uv rays, and have a shatterproof, wear, etc.
5 sunglasses color besides according to their color of skin, face, dress to match, also should choose according to in and out of place. Generally is better to dark gray, dark brown, dark brown and black, blue and purple is poor, because the two lenses will be through more ultraviolet light. Grey lens for any chromatography can balance absorption, wearing glasses can see scenery will only after dark and do not have clear off color, Dark brown lens can filter out a lot of blue light, which can improve visual contrast and clarity, under the condition of air pollution is serious, or foggy effect of wear is preferred, and can smooth light reflection on the surface of the object blocking the light, wear glasses to see small part, is the driver's choice; Dark green lens to heat absorption, bring cool and refreshing feeling, but low penetrability and clarity, suitable for wearing, when the sunshine while driving is unfavorable to wear; Yellow, orange and light red as far as possible need not. Good choice clearly marked on the label 100% uv protection products. Consumers should fully consider the manufacturing cost, sales and service. Twenty or thirty yuan sunglasses, its quality often cannot be guaranteed. To large glasses brand shop or glasses shopping malls counters to choose and buy, can generally make the products in such aspects as quality inspection, all relatived inspections to get a good guarantee.
6 color depth of the lenses are divided into 15%, 34%, 50%, 70%. 15% of the indoor and outdoor can be worn; 34% is suitable for ordinary outdoor environment; 50% for sun and the sea; 70% belong to the welding and other special purposes. How to choose the color of the sunglasses shades? Simple self-test method is to wear sunglasses, in front of a mirror for can vaguely see the pupil of his limit. Color too shallow, filter function is too small; Color is too deep, affect vision and weaken the sense of color. Popular this year the colorful light of the sun glasses, do not use water activities at the beach and the sun is very strong sun wear, and should wear sports sunglasses, the glasses can absorb or reflect more visible light.
7 sunglasses in addition to reduce glare, make the eyes comfortable, main purpose is to prevent ultraviolet damage to the eyes, and whether the lens color and UV protection are two different things, even if the lens color deep, also won't be able to effectively prevent UV, UV resistant are marked so be sure to choose the lens. Usually sunglasses UV index between 96% and 98%.
general regular store had 8 will have sunglasses uv resistance ability of the size of the instrument, through this test, you can know whether the hands of the glasses are helpful to you in the eye health.