High-Quality Clear Glass Lens for Sunglasses
When it comes to the sun proof via sunglasses, the first thing that usually gets into people’s mind is colored sunglasses. In fact, the sun proof enabled by sunglasses is not decided by the shade of colors. Transparent sunglasses have a coating against UV and glare on their glass lenses. Therefore, they can ward off the harmful UVA and UVB in the sunlight to prevent the damage of retina just like colored or dark sunglasses. On the contrary, when dark sunglasses are worn incorrectly, the pupils will enlarge accordingly to increase the absorption of UV. But, it will be ill-timed to wear colored sunglasses on a cloudy day or on public occasions that are unsuitable for sunglasses to appear. We may as well try the colorless sunglasses of Sunphey. Although the lenses have no color, they can satisfactorily block UV, blue light and red light. They can not only protect eyes, but also add a charming touch and beautify the makeup. A comparison of the optical performance of the optical lenses of various materials undoubtedly points to optical glass as winner. The high quality of the clear glass of Sunphey spectacles starts with the production of glass. We strengthen optical performance by using unique processes, innovative formulae and the mineral elements contained in the formulae.
For a pair of high-quality glasses, the quality and performance of the lenses are the most important core value. In addition to the performance of the materials, the performance of lenses includes the optimization of coating, which is also an important process for high-quality lenses. Coating can cause lenses to be dust-free, hydrophotic, oleophobic, scratch-resistant, hardened, and able to obstruct UV, blue light and red light, protect eyes, increase permeability, provide more comfortable reflection resistance.
For example, we optimize the permeability enhancement performance through coating technology. When light gets into the lens through the air and the refractivity of the two media is different, light will generate reflection at the juncture of the two media. The larger the gap of refractivity, the more serious the reflection. Some of the reflection will offset other direct lights, causing even poorer light permeability.
Reflectivity = (difference in the reflectivity of the two media/sum of the reflectivity of the two media)^2
The refractivity of air is 1 and that of glass is 1.5. therefore, there exists a gap of 0.5 in the refractivity between them.
Therefore, when light enters glass from air, the reflectivity is (0.5/2.5)^2=0.04, i.e. 4%.
If something between 1.0 and 1.5 can be added between glass and air, it will effectively reduce light reflection. This is the Anti Reflective (AR) coating. Sunpheyuses the mode of AR coating on both the front and the back and also the method of multilayer coating to gradually strengthen the permeation performance of light. For example, apply a coating of the materials with a refractivity of 1.4, 1.3, 1.2 and 1.1 respectively on the glass surface. The gap between the refractivities is 0.1. If added up, their refractivities will be smaller than the 1.38 refractivity of only one layer of coating. Similarly, the effect will be even better if 50 layers of coating with a refractivity of 0.01 are applied. But, the process of multilayer coating is complex and features a low rate of accepted products, but a high cost. This is also one of the reasons for the large price spread of high-quality lenses. Sunphey clear glass uses the raw materials of world famous brands or equivalent quality. Relying on the advanced coating technology of Sunphey, our lenses have AR coating on both the front and the back in addition to the resistance against scatch, dirtiness and static, interception of blue light and infrared, difficult UV penetration, etc. Our processes follow the standard of the products of famous brands or even better standard to ensure the effect of spectacles, e.g. best perception of the outside world, protection and beautification of makeup.