Sunglasses shopping guide

Sunglasses are a kind of eye care products to prevent the strong stimulation of the sun caused damage to the human eye beauty or reflect the personal style of the special jewelry, people will buy sunglasses according to different needs.
However, some people in the purchase of sunglasses, often feel uncomfortable after purchase, or encounter glasses quality problems. Optician experts remind the public to pay attention to the following points when purchasing sunglasses:
1.First of all, check the quality of the lens to see if the surface of the lens is smooth, there is no warping, wear marks, bubbles. Lens warping will cause vision deviation, uneven or marks, bubbles, can cause dizziness and other discomfort. It should also be noted that the lens should not be too thin, otherwise high temperature deformation will also cause dizziness.
2.You can take the sunglasses to 45 cm away from the eyes, observe the vertical and horizontal lines around the glasses, such as window frames or door frames, and then move the glasses up and down. If the straight line is distorted or wobbled, it indicates that the lens is deformed and should not be purchased.
3.Sunglasses also have an important indicator of light transmission, is the ratio of the luminous flux through the lens and the incident luminous flux, is also an important performance indicator stipulated by a mandatory standard. If you use light-colored sunglasses for shading, the wearer will not be able to obtain the shading effect. The use of sunshade mirrors as light sunglasses affects the clarity of the wearer's vision.
4.Put the sunglasses in front of you, observe distant targets through the lenses, such as window frames or door frames, and then move the glasses up and down, the target should not swing and wave deformation. You can also observe the tube image on the surface of the sunglasses lens under the fluorescent lamp, rotate the sunglasses so that the tube image appears in different parts of the lens, and the tube image is not deformed. Polarized sunglasses on the market, some products use resin polarized lenses with a thickness of 0.7mm, due to thin lenses, it is easy to produce deformation in the assembly, special attention should be paid to the purchase.
5.The color of the lens can not be biased, should make the color of the surrounding environment is not distorted. Before wearing sunglasses, observe red, green, yellow and other colors of the object, and then wear sunglasses, observe the same object, the color of the two observations can not be biased, otherwise it will reduce the ability to recognize traffic lights. For colored lenses, especially brightly colored sunglasses, attention should be paid to this identification.