Lens refractive index and coating technology
Many people often say that they want ultra-thin lenses when they wear glasses, hoping that the glasses are light and light on the face, just like wearing a flat lens. But the so-called "ultra-thin lens" every company has its own definition, and it can also be divided into light and thin, ultra-thin, ultra-thin, and ultra-thin... and the refractive index of the lens is more objective and scientific to express the lens. thickness.The higher the refractive index of the lens is, the thinner the edge of the lens is. It looks even better if it fits on a spectacle frame.
In addition to the advantage of thickness, high refractive index lenses, the lenses will be harder and have better impact resistance because of the higher density. If the spectacle frame that is rimless or needs a car pit is selected, choosing high-refractive-index lenses can reduce damages or cracks the edge angle of the lens.
The following is the thickness of different refractive index lenses under 500 degree myopia:
Starting from the 1.5 lens, the edge of the lens is reduced by about 0.7mm to 1.67 lens; the edge of the 1.74 lens is about 0.3mm smaller than the 1.67 lens.
In theory, a perfectly polished lens will reflect approximately 10% of the light. Coating the lens can greatly reduce the reflection. After many years of development, the coating technology has evolved from single-layer coating to multi-layer coating. After entering the digital design and the nano-level manufacturing process, the reflectivity can be reduced to 1-2%. Through different coating technologies, it can also provide anti-fogging, anti-blue light, anti-ultraviolet, anti-scratch (surface hardening), water repellency, anti-static and other functions.
Our most entry-level lenses are equipped with excellent coatings. Provide anti-reflective, anti-ultraviolet, anti-scratch (surface hardening) and other properties. You can choose the lens from thin to extremely thin.