The role of sunglasses
Ultraviolet rays can damage the cornea and retina, and high-quality sunglasses can completely eliminate ultraviolet rays.
When the eye receives too much light, it will naturally shrink the iris. Once the iris shrinks to its limit, people then need to squint. If there is still too much light, such as sunlight reflected from snow, it will damage the retina. High-quality sunglasses can filter out up to 97% of the light that enters the eye to avoid damage.
Certain surfaces, such as water, can reflect a lot of light, and the bright spots produced in this way can disturb the line of sight or hide objects. High-quality sunglasses can use polarization technology to completely eliminate such glare. We will introduce polarization technology later.
Certain frequencies of light will blur the line of sight, while other frequencies of light can enhance contrast. Choose the right color for the sunglasses, so that it can get better results in a specific environment.
If sunglasses do not provide UV protection, they will expose you to more UV rays. Cheap sunglasses filter out part of the light, causing your iris to open to receive more light. This will also allow more ultraviolet rays to enter, increasing the damage caused by ultraviolet rays to the retina.
Therefore, there is indeed a difference between various sunglasses. For a specific use environment, choosing suitable and high-quality sunglasses will provide you with the greatest protection.
According to international standards, sunglasses are classified as personal eye protection products. The main function of sunglasses is to block the harsh sunlight. However, international standards subdivide sunglasses into "fashion mirrors" and "general purpose mirrors". The quality requirements for "fashion mirror" in the standard are relatively low. Because the "fashion mirror" mainly emphasizes style, the wearer pays attention to decoration rather than protection. In the standard, the quality requirements for "general purpose mirrors are relatively strict, including requirements for UV protection, as well as index requirements for diopter and prism.
