There is a popular saying: "The eyes are the windows of the soul", for a pair of glasses, the lens is the life of a pair of glasses. Myopia occurs, and glasses are inseparable, but the composition of a pair of glasses cannot be without lenses. But what we don't know is that there are many types of lenses, not only the resin lenses we know, so what materials are lenses usually made of? Which material is better? Let's find out together.
What materials are the lenses made of?
- Resin lenses
Resin lenses is a kind of lens that we use more at present, it is composed of a chemical substance with a phenolic structure. Light weight, high temperature resistance, impact resistance, not fragile, no edges and corners when broken, safe, can effectively block ultraviolet rays, and is loved by many glasses wearers.
- Glass lenses.
The clarity of glass lens is slightly higher than that of resin, and it is more scratch-resistant and wear-resistant than lenses of other materials. The lens is thinner, has better optical performance, and is lower in price, but it is heavy and fragile.
- PC lenses
The chemical name of PC lens is polycarbonate, which is a thermoplastic material. PC lens is tough, not easy to break, and impact-resistant, so it is also called safety film. It is also the lightest material currently used for eyeglass lenses, but the price is relatively expensive. In terms of performance, PC sheets are better than resin sheets.
- AC lenses
Both PC lenses and AC lenses are resin lenses, but their processes are different. The difference is that the former is harder and the latter is softer. AC lenses have excellent toughness, light weight, high perspective, and good anti-fog.
- Nylon lenses
Nylon lenses are made of nylon. Nylon lenses have very high elasticity, excellent optical quality, and strong impact resistance. They are usually used as protective items.
How to choose the best lenses?
1.Determine the efficacy.
At present, there are many functions of lenses, but the most choices are anti-blue light lenses. If you choose anti-blue light lenses, you generally choose lenses that filter 30% of blue light, which can block part of the harmful blue light produced by the screen. Blue light filter lenses with a filtering effect of 20% to 30% are indistinguishable from ordinary lenses in appearance, but if they are high-efficiency lenses that filter more than 50% of blue light, the appearance will appear yellow.
2.Bifocal lenses.
This kind of lens is only divided into the upper far vision zone and the lower vision near zone, without the intermediate progressive zone. The advantage is that the field of view is wider than that of progressive multi-focal lenses, which is very suitable for people who need to see near; but the disadvantage is that there is an obvious dividing line in the center of the lens, which is not suitable for people who pay attention to the appearance; if students prevent myopia from deepening If you only want one pair of glasses, bifocal lenses are better than progressive multifocal lenses because the former have a better close-range field of vision.
3.Color-changing lenses.
This kind of lens will turn black in the sun, just like sunglasses that block the strong light from shining on the eyes, it is very helpful for people who often move in the sun, it makes the eyes feel comfortable with soft light, and it can also prevent the eyes from being too strong of sun damage.
Different lenses also have different functions. Generally, the material of the lens is resin. Secondly, we can choose the lens according to our own needs. Another reminder, when choosing lenses, you should choose a regular optical shop to choose, so as to ensure that the lenses
