In summer, many people go out fully armed and wrap themselves up tightly to protect themselves from the sun. But they may overlook a very important part of the body that also needs sun protection - the eyes .

You should know that once the eyes are sunburned by ultraviolet rays, it may be more troublesome than sunburned skin. Not only is it easy to cause corneal lesions, cataracts and other eye diseases, some may even require surgery to recover.

Eyes, which are very sensitive to ultraviolet rays, will "save themselves" when exposed to the scorching sunlight. They will subconsciously activate the body's "light alarm" system, that is, squint their eyes to minimize the damage caused by strong light.

In this case, it is recommended to wear sunglasses to effectively prevent ultraviolet radiation invasion.

How to choose sunglasses? This article will tell you!

1. Look for the signs!

A qualified pair of sunglasses must at least effectively protect against ultraviolet rays.

To determine the UV protection of sunglasses, first look at the UV protection mark:

In terms of UV protection effect, 100% UV absorption > UV400 > UV protection/UV/UV protection.

You also need to look at the implementation standard number on the product information sheet. It is recommended to choose products that comply with the national standard GB 39552.1-2020 or the industry standard QB 2457-1999 . Try not to buy sunglasses with incomplete labeling.

2. Different types of sunglasses are suitable for different scenarios

Sunglasses are also called visors or dark glasses. When you are outdoors, especially in areas or seasons with strong sunlight, in addition to protecting against ultraviolet rays, you must also prevent strong light from irritating your eyes and wear visors to block the sunlight.

To protect against strong light , you need to look at the light transmittance of the sun lens. As shown in the figure below, sun lenses that meet the requirements of the national standard GB 39552.1-2020 include light-colored sunglasses, sun visors, and special-purpose sunglasses. According to the light transmittance, they can be divided into 0, 1, 2, 3, and 4 categories. The higher the grade, the better it can block light .

Note: Transmittance refers to the ratio of transmitted luminous flux to incident luminous flux, and is used to indicate the effect of sun lenses in blocking sunlight and glare.

Purchase Tips :

✔For daily use, choose category 2 or 3 sun lenses;

✔ For driving scenes, choose sun lenses of category 0, 1, 2, or 3;

✔For outdoor activities, choose Category 4 sun lenses.

3. Lens shape and size are also important

Many friends like to buy some "Internet celebrity" sunglasses. The lenses of these sunglasses are often in strange shapes and look cool when worn. They can be said to be a must-have fashion item for taking pictures.

However, if the curvature of the sun lens does not fit the face shape, or the lens is too small or too large, it may easily leak light . Even if the lens has qualified UV protection, the sun protection effect may be greatly reduced.

When purchasing, it is recommended to first check whether the lens size is suitable for you. Health is more important than appearance.

Have you learned how to choose sunglasses?