Ultraviolet rays can damage the cornea and retina, and high-quality sunglasses completely eliminate ultraviolet light.
When the eye receives too much light, it naturally shrinks the iris. Once the iris has contracted to its limit, then people need to blink. If the light is still too much, such as the sunlight reflected from the snow, it will damage the retina. High quality sunglasses filter up to 97% of the incoming light to avoid injury.
Some surfaces, such as the water surface, can reflect a lot of light, and the resulting bright spots can disturb the line of sight or hide objects. High-quality sunglasses can completely eliminate such glare using polarizing technology, and we will introduce polarizing technology later.
Light at certain frequencies blurs the line of sight, while light at other frequencies enhances contrast. Choose the right color for your sunglasses to get the best results in your particular environment.
If the sunglasses don't provide UV protection, it will expose you to more UV light. Cheap sunglasses filter out some of the light, causing your iris to open to receive more light. This will also allow more UV rays to enter, increasing the damage that the UV rays cause to the retina.
Therefore, there is indeed a difference between the various sunglasses. Choosing the right, quality sunglasses will give you maximum protection for your specific environment.
According to international standards, sunglasses are listed as a category of personal eye protection products. The main function of sunglasses is to block the glare of the sun. However, international standards have subdivided sunglasses into "fashion mirrors" and "general purpose mirrors." The quality requirements for “fashion mirrors” are relatively low in the standard. Because the "fashion mirror" mainly highlights the style, the wearer pays attention to the decoration, not the protection function. In the standard, the quality requirements for general purpose mirrors are strict, including the requirements for UV protection, as well as diopter and prismaticity.