AR coating: Better vision, better appearance
All eyeglass lenses reflect some light, reducing the amount of light that enters the eye to form visual images. This can have an impact on vision, especially under low-light conditions, like when driving at night. Lens reflections can also cause glare, further reducing vision in these situations.
The amount of light reflected depends on the lens material. Conventional glass or plastic lenses reflect about 8% of incident light, so only 92% of available light enters the eye for vision. Thinner, lighter lenses made of high index materials reflect up to 50% more light than regular glass or plastic lenses (up to 12% of available light).
Anti-reflective (AR) coating reduces lens reflections and allows more light to enter the eye for better night vision. Regardless of the lens material, eyeglass lenses with AR coating transmit over 99% of available light to the eye.
By eliminating surface reflections, anti-reflective coating also makes your lenses nearly invisible. This greatly improves the appearance of your eyewear and allows others to see your eyes, not the reflections in your glasses.
When cleaning lenses with anti-reflective coating, be sure to use the products recommended by your optician. Because AR coating eliminates reflections that can hide small scratches, you'll want to take care not to scratch AR-coated lenses, as scratches on these lenses may be more visible than scratches on an uncoated lens.
No eyeglass lens material – not even glass – is scratch-proof. However, a lens that is treated front and back with a clear, hard coating does become more resistant to scratching, whether it's from dropping your glasses on the floor or occasionally cleaning them with a paper towel. Kids' lenses, especially, benefit from a scratch-resistant hard coat.
Nearly all high index lenses (including polycarbonate) come with a factory-applied scratch-resistant coating for added durability. This coating is optional for regular plastic lenses. However, to safeguard your investment in your eyewear, scratch-resistant coating should be considered for all eyeglass lenses. The only exception is glass lenses, which are naturally hard and scratch-resistant.
To further protect your eyeglasses from scratches, keep your glasses in a protective case when you're not wearing them. Also, never clean your lenses without first rinsing them with a cleaning solution or water. Rubbing a dry, dusty or dirty lens with a cleaning cloth or towel can cause scratches, even on lenses with a scratch-resistant coating.