Photochromic myopia glasses

There are more and more people with myopia. We found that most of them are students. Many children have bad study habits. They read, do homework and watch TV very close. Such bad habits will cause myopia for a long time. Myopia requires wearing glasses. There are really many types of myopia glasses now, especially a kind of color-changing myopia glasses is very popular.

When choosing myopia glasses, some people feel that some of the previous glasses are too monotonous, and they have to be fashionable even if they wear glasses. Now there is a kind of photochromic myopia glasses, that is, the lenses are colored. Generally, the lenses of such glasses can change to gray and brown.

Myopia glasses are concave lenses. The image formed by a concave lens is always smaller than the object and is an upright virtual image. Concave lenses are mainly used to correct myopia. Myopia is mainly caused by the deformation of the lens, which causes light to gather in front of the retina prematurely. The concave lens has the function of diverging light, forming an upright, reduced virtual image, which lengthens the image distance and falls exactly on the retina.

Glasses power: The refractive strength of glasses lenses is generally expressed in degrees. One dioptre is equivalent to 100 degrees as generally known to people or opticians, or D 1.00 in non-Chinese countries (D here stands for Dioptre rather than Degree). The more severe the vision problem, the stronger and thicker the lenses required.

What is the principle of photochromic myopia glasses? In the process of making photochromic myopia glasses, some silver halides need to be added, which are used as photosensitizers. These small particles of silver halides are evenly distributed in the lens. When ordinary light shines on the silver halide, the color of the lens remains transparent and clear and does not change. When strong ultraviolet rays shine on the silver halide, it will be decomposed into silver atoms and halogen atoms. The more silver atoms, the darker the color, and the fewer silver atoms, the lighter the color.

Generally, the price of photochromic myopia glasses on the market is about several hundred yuan. Of course, the prices of photochromic myopia glasses launched by different brands and different merchants will also vary. For example, if you buy glasses in Shanghai, it is much cheaper to buy glasses online. Photochromic myopia glasses are very necessary for outdoor workers, but they are not very useful for ordinary office white-collar workers.

Photochromic myopia glasses are more expensive than ordinary myopia glasses. Such glasses are also loved by many young people. The lenses will change color when exposed to ultraviolet rays, which is really cool. However, there are many precautions when wearing such glasses. Such glasses are only suitable for myopia within 400 degrees, and you should also choose some good brands to avoid unnecessary damage to the glasses.