The choice of myopia lenses_Lens knowledge
The choice of myopia lenses is a concern of many friends, which involves the choice of lens material, the refractive index of the lens, and the quality of the lens. Whether it is lenses or frames, if it is related to glasses, it is best to go to a glasses store. No matter which aspect is more secure, let's learn about the choice of myopia lenses. The first is optometry, which is a must for glasses. It is very important to choose a professional optical shop. The accuracy of optometry has a great influence on the matching of glasses. It is better to choose those optical shops with good reputation, such as OULE glasses network. After confirming your prescription, you can choose the lens. Choose from the index of refraction. The higher the index of refraction, the thinner the lens and the more expensive it will be. For different degrees of myopia, the refractive index of the selected lenses is not exactly the same. For friends with myopia between 300 and 600 degrees, we recommend you to use lenses with a refractive index of 1.53 to 1.61; for friends with myopia between 600 and 900 degrees, we recommend You should use lenses with a refractive index of 1.61~1.67 or higher; friends with myopia above 900 degrees are recommended to use lenses with a refractive index of 1.67 or higher. If you have a high degree of myopia, you need to choose a lens with a high refractive index. If you choose a relatively low refractive index, the lens will be very thick, which not only affects the appearance, but also affects the wearing effect. Therefore, friends with high myopia need to choose aspherical high refractive index lenses, which are very thin. In addition, the aspheric lens has a very clear field of view, which reduces the aberration of the edge of the lens, and is also very beautiful. Generally speaking, friends with high myopia can choose lenses with refractive index nu003d1.70, 1.80 or even 1.90 (this refers to glass lenses. The current highest refractive index of resin glasses is 1.74), which can reduce the thickness of the lenses. If you choose from the material, because the same degree, if the lens material is different, the refractive index is different. Compared with lenses of the same degree and diameter, the thickness of resin lenses is thicker than ordinary glass lenses. Friends with high myopia are more suitable for choosing glass lenses. Resin lenses are safer and light, and the lenses are coated with anti-radiation films, which are more suitable for children.