Tips: What is the role of color glasses?

The part of the photochromic lens is similar to the ordinary lens in terms of its chemical composition. The difference is that the photochromic lens adds silver halide or photosensitive organic substances. Silver-plated lenses are made of light-sensitive silver halide particles, a small amount of copper oxide and common lens glass materials. When the silver halide encounters sunlight, a reversible photochromic reaction occurs. The silver halide absorbs all ultraviolet rays in the sunlight. Further, the following reactions take place: under the catalysis of ultraviolet rays: AgX2Ag+X2 (X is a halogen element including fluorine F, chlorine Cl, bromine Br, and iodine I). Since the silver atom particles can absorb visible light, the lens becomes dark gray. When the lens is in a weak light state, under the catalysis of copper oxide, the following chemical reaction occurs: Ag+X2AgX2, so the lens becomes colorless again.

However, since the glass lens has a curved shape, it is often thin in the middle and thin, and the silver halide is uniformly distributed. When the color is changed, the relatively thick portion has a darker color, and the color change is uneven, which impairs the beauty of the lens. The resin photochromic lens directly on the surface of the ordinary resin lens plated with a layer of discoloration material, evenly penetrate into the lens surface during processing, so that it changes color evenly under the sunlight, this type of color-changing glasses have many colors, which can turn brown, pink, etc. Depends on the choice of photosensitive material.

The main role of color-changing glasses is to absorb ultraviolet rays, thereby protecting eyesight. UV damage to the human eye is all-encompassing and can lead to abnormal proliferation of the conjunctiva of the eye, oxidation of proteins and lipids of the cornea and damage of the lens, cortical cataracts of the lens, etc., and also cause keratitis and macular lesions. Today, as the ozone layer at high altitude becomes thinner and thinner, the ultraviolet light content in the sunlight continues to rise and damage to human eyes is much greater than before. Therefore, color-changing glasses can reduce eye damage.

In addition to the function of filtering ultraviolet rays, color-changing glasses can also be used as sunglasses (in the sun, the color becomes darker), especially in the case of dazzling light, ordinary glasses can only be worn with glasses, and you cannot look directly at the sun. Even so , The eyes are easy to dry, fatigue, but also lead to long-term smaller pupils, glasses refractive system disorders, a great impact on vision.

Of course, the use of color-changing glasses in the room is no different from ordinary glasses because the amount of ultraviolet light in the light emitted by a typical indoor lamp is negligible. Therefore, wearing a pair of color-changing glasses can always protect your eyes, whether it is nearsightedness or not, in the environment such as snow walking, hot sun, and driving.