Anti-reflective coating (also called AR coating or anti-glare coating) improves both your vision through your lenses and the appearance of your glasses.
AR coatings are similar to the coatings found on microscopes and camera lenses. They consist of several layers of metal oxides applied to the front and back lens surfaces. Because of the layering effect, AR coatings sometimes have a hint of green or purple color, depending on the individual manufacturer's formula.
Each layer is scientifically calculated to block reflected light. The result is that you'll see a reduction in glare, annoying reflections and halos around lights. This is a great safety benefit when you're driving at night.
Also, anti-reflective coating reduces both internal and external reflections on the lenses themselves, creating a nicer cosmetic appearance. Internal reflections appear as rings that make lenses look thick. External reflections mask your eyes from a clear, complete view when someone is looking at you. So with an anti-reflective coating, reflections are eliminated and eyeglass lenses look thinner or non-existent and your eyes are more visible so you can make better eye contact with others.
Anti-reflective coating is beneficial for virtually everyone who wears eyeglasses. Also, research shows wearing AR coated lenses improves night driving vision and increases comfort during prolonged computer use (compared with wearing uncoated lenses).
AR coating is especially beneficial if you choose high-index lenses. These thinner, lighter lenses reflect more light than regular plastic lenses unless anti-reflective coating is applied.
Anti-reflective coating is also beneficial when applied to the back surface of lenses in sunglasses because it eliminates reflections of sunlight into your eyes from the lenses when the sun is behind you. (Since the purpose of sunglasses is to reduce how much light enters your eyes and because you aren't concerned about making eye contact with others when wearing shades, there is no benefit to having AR coating applied to the front surface of sunglass lenses.)
Most premium anti-reflective coatings include a "hydrophobic" surface layer that prevents water spots from forming and makes the lenses easier to clean. Some AR coatings also include an oleophobic surface layer that repels skin oils and makes it easier to remove smudges for the lenses.
When cleaning AR-coated lenses, use only products that Eyeglass House recommends. Lens cleaners with harsh chemicals may damage the anti-reflective coating.
Also, don't ever attempt to clean AR-coated lenses without wetting them first. Using a dry cloth on a dry lens can cause lens scratches. And because anti-reflective coating eliminates light reflections that can mask lens surface defects, fine scratches will be more visible on AR-coated lenses than on uncoated lenses.