Contact Us
TEL: +86-511-86229810
Address: No.1 of Bawei Road, Danyang City, Jiangsu Province, China
Home > Knowledge > Content
The cardinal meaning of spectacle lenses
Sep 11, 2017

1. Refractive index-reflects the lens of the light refraction of the ability of the resin lens in general between 1.49 ~ 1.74, glass lenses in general between 1.523 ~ 1.9, the refractive index of the larger the lens thinner, more beautiful, of course, the price is more expensive.

2. Proportion-reflects the unit volume lens weight, resin lenses generally between 1.19 ~ 1.4, glass lenses between 2.4 ~ 4.1, the proportion of the value of the smaller the weight of the lens lighter.

3. Anti-UV-reflecting the lens of UV resistance, in order to block the wavelength of ultraviolet light to express, generally between 350~400, the higher the range of values, the greater the ability to prevent UV lenses.

4. A--also called dispersion coefficient, reflecting the dispersion of the lens, generally between the 30~58, the higher the numerical value of the lens of the smaller the dispersion, the lens of the three prism effect on the white light decomposition into colorful influence is smaller.

5. Curvature design-spherical and aspherical two, aspheric image quality is better, the lens thinner, but the optical center requires precise, can not move the heart.

6. Transmittance--in general, no coating of the lens transmittance of 87%-88%, and the coating of the lens transmittance can reach 92%-95%, of course, in addition to the light transmittance with the reflective film, with the lens material, refractive index is also related to the same refractive index good brand transmittance can reach 98%-99%.

7. Film Layer-single layer and multi-layer? Single layer generally only add anti-hard film, multilayer bottom film, hard film, coated reflective film, hydrophobic anti-fouling membrane, and good process has 7, 8 layers.

Previous: What is a discoloration lens

Next: Basic introduction of spectacle lenses