To check the quality of the lens, sunglasses to get about 45 cm away from the eyes, through the the glasses observed around the vertical and horizontal lines, such as a window frame or door frame, and then the glasses up and down to move back and forth, if found straight distort or swing Description The lens distortion. Uneven bubbles lenses, lens uneven wear dizziness, uncomfortable to see things, deformation, not buy. Sunglasses flat on the counter, if the glasses can not be placed on a smooth frames! Pale colored sunglasses filter effect, too deep and affect vision .. buy Ray Ban gray, Ray-Ban green, blue-gray true shade of lens sunglasses, because these relatively soft colors, watching nature does not change color! make the eyes from infrared, ultraviolet radiation, the color of the glasses should be sufficient depth, usually in summer use of gray , green or brown lenses.
The quality of the lens in the first place: through clarity; lens formation. Choose sunglasses and must choose UV, look at the mirror or tag does not indicate the anti-UVA, UVB logo. SO sunglasses color to light gray, brown or smoke color is superior, followed by green, amber, red powder lines only as a sun or snow. Wearing sunglasses in the mirror, can vaguely see the pupil Description Color moderate depth == the more intense the more light should choose to wear dark sunglasses, generally better in dark gray, dark brown and black, followed by selection. Bright lenses may not be suitable for everyone, bad choice, could harm vision, if possible, before the selection of sunglasses can consult the ophthalmologist views to the UV index is the UV filter effect, it is important to a standard The vast majority of sunglasses, UV index between 96% -98%, dark lenses than light-colored lenses better. Generally, 100% of the UV index is unlikely.
Sunglasses quality refers to the quality of the lens. Common standards in the world for food and medicine and health Inspection Agency (FDA) standards. Lens to protect the light transmittance at the same time, it is necessary to filter out more than 90% of the sun’s ultraviolet rays, lens paste the UV-100PROTCT10N “label, when 100% UV filtering, paste the UV-400PROTCT10N” label, the sun goes down is best to remove the sunglasses, or in low light vision will be affected. Generally diopter more than 15%, there will be a feeling of dizziness when worn, but some lenses are defective, or even recycled, the lens with a certain degree of myopia, and some more than 10 degrees, and some two dozen general feeling does not come out, must be regular optical shop optometry can be detected.