Sunglasses, also known as sunshades, are used for shading. In the sun, people usually adjust the pupil size to adjust the luminous flux. When the light intensity exceeds the eye’s ability to adjust, it will cause harm to the human eye. Therefore, in outdoor activities, especially in the summer, sunshades are needed to block the sunlight to reduce the fatigue caused by eye adjustment or the damage caused by strong light stimulation.
Sunglasses are a kind of eye care products that prevent eye damage caused by strong sunlight. With the improvement of people’s material and cultural level, sunglasses can be used as a special accessory for beauty or personal style.
Since the sun’s rays reaching the earth’s surface contain ultraviolet rays, the cornea and crystals of the human eye are the most vulnerable to ultraviolet damage, and “cataracts” are eye diseases closely related to them. Due to the destruction of the ozone layer by the environment and the increase in outdoor activities in summer, the damage of ultraviolet rays to the human eye cannot be ignored. Wearing sunglasses is a good way to protect your eyes from UV damage, but pay special attention to sunglasses.
In accordance with international standards, sunglasses are listed as a category of personal eye protection products, because sunglasses are worn in the summer, the main function 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. The quality requirements for “general purpose mirrors” are more stringent in the standard, including requirements for UV protection, as well as diopter and prismaticity.
To clarify polarizers and non-polarized sunglasses, you must first introduce some knowledge of polarizers and unpolarized sunglasses. In fact, polarizers are also considered to belong to the category of sunglasses, but polarizers are a relatively high-end type of sunglasses. Polarizers have the effect that ordinary sunglasses do not have. This function can effectively block and filter out various polarized lights that are harmful to the eyes.
The so-called polarized light is the irregular reflected light generated by the light passing through the uneven road surface, water surface, etc., also called glare. When these lights directly illuminate the human eye, the eyes will be uncomfortable, prone to fatigue, and will not be able to look at the objects for a long time. The clarity of the objects viewed is obviously insufficient.
Sunglasses only use the effect of dimming, because the general lens cannot filter the light, so it can only reduce the intensity of glare, ultraviolet light, etc., and can not completely block these harmful light, so its function is only to reduce eye damage, but the general sun The biggest advantage of glasses is the popularity. Because of its polarizing properties, polarized lenses completely block the glare caused by various factors such as scattering, inflection, and reflection. At the same time, it can completely block the ultraviolet light harmful to the human eye, so that when the person is acting under strong light for a long time, the eyes are not easy to get tired, and the function of real protection is achieved, and the things seen can be made clearer and three-dimensional.
Because polarized sunglasses have the function of polarizing light, they can block all harmful light without affecting the transmission of visible light, and can truly protect the eyes. In addition to the basic UV protection function, polarized sunglasses vs non-polarized also have anti-glare, reflective light on the road surface, scales on the water surface, etc., suitable for driving, fishing, traveling, and daily wear.