Anti-reflective glass woking principle
AR glass is also called high transmittance and low reflectivity glass,which is a manufactured through coating two to multiple transparent anti-reflection layers on single or double sides of glass by advanced vacuum coating technology. A common problem with prescription glasses and sunglasses is called back-glare. This is light that hits the back of the lenses and bounces into the eyes. The purpose of an anti-reflective (AR) coating is to reduce these reflections off the lenses. In bad cases, you can actually see the reflection of your eye in the lens. Similar to a scratch-resistant coating, AR is made of a very hard thin film that is layered on the lens. It is made of material that has an index of refraction that is somewhere between air and glass. This causes the intensity of the light reflected from the inner surface and the light reflected from the outer surface of the film to be nearly equal. When applied in a thickness of about a quarter of light's wavelength, the two reflections from each side of the film basically cancel each other out through destructive interference, minimizing the glare you see. AR coatings are also applied to the front of prescription eyewear and some sunglasses to eliminate the "hot spot" glare that reflects off the lens.