Classification of lens materials

Glass lenses, including optical glass lenses and high refractive index lenses (commonly known as ultra-thin), have high hardness and wear resistance, and generally their quality and parameters do not change with time, but the impact resistance and weight of glass lenses are slightly inferior to resin lenses.

Resin lenses are generally much lighter than glass lenses, and the impact resistance is better than glass, uv protection, but its surface hardness is lower, more easy to be scraped. Resinous lens and lens of coating film because its characteristic is softer, should notice to do not let lens face contact hard thing at ordinary times so, had better use clear water first when scrub (or mix a few wash clean essence) clean, try cloth or high-quality cotton paper to absorb the water drop on lens with special next. In addition, in poor environmental conditions should be careful to use coated lenses, so as to avoid contamination difficult to clean.

Cosmos (PC) lens: high index of refraction, strong, but easy to wear. Most used for children's lenses, frameless assembly or athlete's eye protection.

What are the advantages of lens coating?

Coating lens can reduce the reflected light of the lens surface, see things clearly, reduce the reflected light of the mirror, increase the transmission rate of light, also solve the problem of wearing glasses under strong light, increase the aesthetic feeling. Coated glasses can prevent the harm of ultraviolet ray, infrared ray and X ray to vision. Wearing coated glasses is not easy to fatigue. The vision of the staff in front of the fluorescent screen can be protected.

Coating resin lens in addition to should avoid scratch touch high temperature, should also avoid acid lampblack and other erosion, such as in daily life had better not wear a mirror to cook, especially when ventilation is not big lampblack; Also cannot wear at the same time (take) lens to enter (near) environment of hot water shower, when placing temporarily normally lens convex surface is up, should put glasses inside box when carrying, do not put pocket casually or in hanging bag, make film layer abrade extremely easily in that way.

How long is the service life of the lens?

If the lens has no scratches, can it be used continuously? The answer is no. Resin lens processing is high temperature liquid monomer or uv curing, with longer life cycle, the change of environment and temperature, film layer on the surface of the lens and the lens material itself can change the physical, membrane layer under a microscope to see will be uneven, local luminosity and fitting materials itself has produced differences, lead to the light scattering, comfort, with long time will have the symptoms of dry eyes, distention, this time, you need to replace the lens. It takes about two to three years.

Spherical lens and aspheric lens

In the traditional spherical lens, not only the lens is thicker, but also things are distorted through the periphery of the lens, which is called aberration. Through the spherical lens to observe the wearer, can also clearly find the deformation of the face contour phenomenon. Aspheric lens can not only reduce the thickness of the center and edge of the lens, but also make the lens thinner and eliminate peripheral aberration, thus giving the wearer natural vision. For consumers with high vision degree, aspheric lens may be more suitable.

Compared with aspheric surface, aspheric lens of the same material and degree is flatter, thinner, more realistic and more natural and comfortable. If you look at the lamp tube to see the shape of lens coating film, generally aspheric lens reflection tube is straighter (except for high-diopter lens); Due to the different curvature of the surface of spherical lens, the shape of lamp tube is more curved.