Views:216 Author:Site Editor Publish Time: 2020-08-25 Origin:Site
With the increase of myopia, it is inevitable to change glasses. A pair of fashion blue light glasses will add points to the external image. To replace the glasses, you must try on and choose them by yourself. So, how can you choose the right glasses for yourself?
Lens materials are mainly divided into glass, resin and PC. although the optical performance of glass lens is good, it is fragile and has hidden dangers to eye health. Few people are equipped with glass lens now, while more and more people choose resin lenses. Although resin lens is more expensive than glass and PC lens, whether from performance or health considerations, resin lenses are the good choice.
With the deepening of people's understanding of the eyes, it is found that our eyes are not a spherical shape. Aspherical lenses can help us achieve better visual quality. Aspherical lenses are also thinner, lighter and clearer than equal-degree spherical lenses.
The aspherical design of lens is a kind of design which can make up the defect of the spherical design of lens. In theory, the lens with this design can achieve exactly the same visual effect as the front eye. In addition, the curvature of the lens is reduced and the thickness of the lens is reduced. Convex or concave mirrors for myopia or hyperopia have only one radius of curvature, the convex surface of the inner surface tc lens for astigmatism has a radius of curvature, and the concave surface has two perpendicularly intersecting radii of curvature.
The surface radian of aspherical lens is designed by aspherical surface. The advantages of this design compared with the spherical design lens are as follows.
The aspherical lens with special coating treatment has more perfect visual performance, showing clearer and more comfortable visual effect.
You'll barely feel the weight of the aspherical lens when you put it on, and you can enjoy the ease it gives you.
3. More Natural
The aspheric design is more natural, with less visual distortion and a more realistic view.
The values of 1.56, 1.61, 1.67, 1.70, 1.74, etc. marked on the lens refer to the refractive index. The higher the refractive index, the thinner the lenses of the same degree, and the stronger the dispersion, that is, the visual effect will be reduced. The edge of the lens with high refractive index is thinner than that with low refractive index. The thinner the lens, the lighter the weight, and the higher the price.
When we match anti blue light blocking glasses, another data is necessary, that is the interpupillary distance. Interpupillary distance is the distance between the center of the pupils of our eyes when we look straight ahead. Because the principle of matching glasses is that the center of each lens must correspond exactly to the center of our pupils. After knowing the pupil distance, the optician can use the machine to grind the lens.
If the interpupillary distance is wide, you can choose a glasses frame with a wide bridge of nose. Try to make the thinnest point of your lens correspond to the center of the frame so that you can get thin reading glasses.
When matching glasses, we must be responsible for our own eyes. It is a good choice to choose a large chain of glasses stores for matching glasses, or go to the hospital for optometry, and then go to some famous professional online matching platforms for matching glasses. Knowing some knowledge about glasses is very helpful for consumers to choose glasses correctly. For example, blue light blocking computer glasses can protect the eyes to a certain extent, especially for those who stare at the electronic screen for a long time. When we are reading a book or a newspaper, we can use ultra thin reading glasses to adjust and see the near objects clearly.