Types of lenses by material

21-08-20 16:36:17产品知识BY ADMIN

The types of lenses for glasses can be divided into materials, functions and spherical shapes. If types of lens for glasses by material , they can be divided into glass lenses, resin lenses, and crystal lenses. This article mainly describes types of lenses by materials, its technology, functions, and applications, etc.

Types of lens by material 1: Glass lens. Glass is the earliest material used as spectacle lens. Although the current lenses are generally resin lenses, glass lenses played an irreplaceable role in that era. Glass lenses are divided into glass sunglasses lenses and glass optical lenses. The advantage of glass lens is that it is very hard and the permeability is high, but the disadvantage is that it is relatively heavy and it is the heaviest lens of all types. Applicable: acetate sunglasses, metal sunglasses. Among the more famous brands, Ray-Ban is one of the brands with the most glass lenses.

Glass lens

Types of lens by material 2: Resin lens. Light weight, not fragile, and safety are the biggest characteristics of optical resin materials. Its weight is about one-half of the glass lens; its impact resistance is 10 times higher than that of glass, its chemical stability and light transmittance are also better, it absorbs ultraviolet rays and is easy to process. However, the disadvantages of resin lenses are relatively low hardness, easy scratches, and poor heat resistance. But at present, there are mature processing technologies for these shortcomings of resin lenses. As long as the surface is covered with various functional films, the above shortcomings can be greatly solved. For example, attaching a hard film can increase the hardness of the lens and make it more resistant to scratches. Common resin lenses include CR39 lenses, nylon lenses, PC lenses and AC lenses. CR39 lens and nylon lens are widely used in glasses of various materials, such as acetate eyewear and metal sunglasses and buffalo horn eyewear, etc. PC lenses are mostly used in injection eyewear and TR90 eyewear, and AC lenses are generally used as optical frames. When customers buy eyewear, It is usually replaced by a myopia with a degree. 

 Resin lens

Applicable type: Widely used in eyewear of various materials, including acetate eyewear, metal eyewear,  titanium eyewear, injection eyewear and horn eyewear, etc.

Types of lens by material 3: Crystal lens. Crystal is a transparent quartz crystal, the main component is silicon dioxide. Its refractive index and density are higher than glass lenses. The advantages of crystal lenses: high hardness, high temperature resistance, friction resistance, and moisture resistance. The disadvantages are: high hardness, difficult processing, heavy weight, and expensive. Most of these natural crystals have impure texture and uneven color, which reduces the light transmittance. Its optical performance is not as good as glass, and it is basically not used at present.

Crystal lens

As an eyewear manufacturer, the most common classification is based on materials. The technicians of the factory will match the lenses according to the different materials and designs of the frames. For example, we generally consider CR39 lenses and nylon lenses for medium and high-end acetate eyewear and metal eyewear. if it is half-frame or rimless, then nylon lens must be used. The above is the general type of lenses. In our other articles, we will conduct a more comprehensive analysis and study of each main types.