Nowadays, there are many kinds of sunglasses on the market and different grades. This makes many consumers caught off guard when choosing, and it also brings a lot of confusion. Why are the prices different for the same glasses? A pair of sunglasses looks very simple. That is to say, there are two colored glass or plastic sheets in a certain plastic or metal frame. In fact, the two glass sheets can have a lot of differences. When you use sunglasses, these differences will also have a great impact on you. . So, the choice of sunglasses? Let's take a look with the editor below. Sunglasses are also called sun-shading mirrors. They are used for shading. People usually adjust the luminous flux by adjusting the size of their pupils in the sun. When the light intensity exceeds the adjustment ability of the human eyes, it will cause damage to the human eyes. Therefore, in outdoor activities, especially In summer, many people use sunshade glasses to block the sun to reduce fatigue caused by eye adjustment or damage caused by strong light stimulation. Sunglasses are a kind of vision health products to prevent the strong stimulation of sunlight from causing damage to the eyes. With the improvement of people's material and cultural level, sunglasses can be used as special accessories for beauty or to embody a style. Since the sun's rays reaching the earth's surface contain ultraviolet rays, the cornea and lens of the human eye are the most susceptible ocular tissues to ultraviolet rays, and cataract is an eye disease closely related to it. Due to the destruction of the ozone layer by the environment and the increase of people's outdoor activities in summer, the damage of ultraviolet rays to human eyes cannot be ignored. Wearing sunglasses is a better way to protect the eyeball from ultraviolet rays, but special attention should be paid to the choice of sunglasses. The first choice of sunglasses is to pay attention to the optometry link. Choose a pair of suitable and comfortable glasses. Accurate optometry is a basic factor. Before fitting glasses, check whether the optician's optometrists have an optometrist issued by the Provincial Optical Industry Association. Or an optometrist certificate. If your optometry is affected by your emotions and physical conditions, you should undergo two optometry within a few days to achieve scientifically accurate optometry results. The second is to pay attention to the choice of glasses materials. Generally, glasses lenses are divided into resin, glass and crystal. Both lenses and frames should have a shelf life. If the lenses and frames are imported materials, they should have an import commodity inspection certificate. Third, when buying glasses, you must read the product quality inspection certificate, the name of the manufacturer, and the address of the glasses you are buying. At the same time, you must obtain a shopping invoice. Once a quality problem occurs, you can protect your legitimate rights and interests. Improper wearing of sunglasses is prone to eye diseases. It is not necessary to wear sunglasses under dark conditions such as cloudy days and indoors. Some people regardless of the occasion, regardless of the intensity of the sun, even at dusk, evening, and when watching movies or TV. Wearing sunglasses will inevitably increase the burden of eye adjustment, cause eye muscle tension and fatigue, loss of vision, blurred vision, and dizziness in severe cases. It is not suitable for babies and children with imperfect visual system development. Wearing sunglasses, except for sunglasses with glass lenses, other sunglasses lens materials are not highly wear-resistant. Users should always pay attention to the surface of the sunglasses. When wear affects the clarity, they should be replaced in time.