Lens refractive index and coating technology

Refractive Index

Many people often say that they want ultra-thin lenses when they wear glasses, hoping that the glasses are light on the face, just like wearing a plano lens. To accurately describe the thickness, we need to know the refractive index of the lens, which is an objective and scientific way to represent the thickness of a lens.

The higher the refractive index, the thinner the edge of a lens is. Then It looks better when it fits on a eyewear.

Coating Technology

Theoretically, a perfectly polished lens will reflect about 10% of the light. By coating the lens, the reflection can be greatly reduced. After many years of development, coating technology has evolved from single-layer coating to multi-layer coating. After entering the digital design and nano level, the reflectivity can be reduced to 1-2%. Through various coating technologies, lens coating can achieve anti-fogging, anti-blue light, anti-ultraviolet, anti-scratch (surface hardening), water repellency, anti-static and other functions.

Each brand has several unique coating technologies such as Crizal Sapphire HR from Essilor, HVLL UVC from Hoya, DuraVision from Zeiss, No Reflection Coat from Tokai, etc... These advanced coating technologies are combined with the design of the lens, bringing more comfortable vision.

Our most basic lenses are equipped with excellent coatings. They provide anti-reflection, anti-ultraviolet, anti-scratch (surface hardening) and other properties. You can choose the lens from thin to ultra-thin.