By the material of the lenses: glass lenses, resin lenses, PC lenses, etc. respectively.
Glass lenses: glass was the first material to be used for spectacle lenses, and the higher the prescription, the greater the thickness of the glass lenses. However, glass lenses also have a major disadvantage: they are easy to break and less safe.
Resin lenses: light weight, unbreakable and safe are the most important characteristics of optical resin materials. However, resin lenses also have disadvantages: they are less hard, more prone to scratches and less heat resistant. There are now mature techniques for dealing with these conditions in resin lenses, as long as they are covered with various functional film layers, which can greatly solve the above deficiencies.
PC lenses: PC lenses, also called space lenses, chemically known as polycarbonate, are tough, not easy to break and can effectively prevent the breaking of lenses during intense sports, while PC lenses are light, with a specific weight of only 2 grams per cubic centimetre, and have a good UV protection, but because of the high price, the trouble of processing and the lack of ideal dispersion control, PC lenses are only available in small quantities on the market.
Post time: Apr-12-2023