A pair of sunglasses looks very simple, that is, there are two pieces of colored glass or plastic in a plastic or metal frame. Is there anything simpler than this? In fact, there are many differences between two glass lenses. When you use sunglasses, these differences will also have a great impact on you. Ultraviolet rays can damage the cornea and retina, and high-quality sunglasses can eliminate ultraviolet rays.

Sunshine is a double-edged sword. On the one hand, it helps to delay the deepening of myopia, and on the other hand, excessive sunlight causes many harm to the eyes. Sunlight is good for eyes: it is mainly because it can stimulate the production and release of dopamine under outdoor sunlight, and dopamine delays the excessive growth of eye axis length. During outdoor activities, children's eyes usually focus on distant objects, so that the ciliary muscles can relax and the eyes can rest, which can play a role in preventing myopia and delaying the progress of myopia.

When the eye receives too much light, it will naturally shrink the iris. Once the iris contracts to the limit state, then people need to squint. If the light is still too much, such as the sunlight reflected by snow, the retina will be damaged. High-quality sunglasses can filter up to 97% of the incoming light to avoid injury.

Some surfaces, such as the water surface, can reflect a large amount of light, and the bright spots thus produced will disturb the sight or hide objects. High quality sunglasses can completely eliminate such glare by using polarizing technology.