Anti-reflection lenses

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Anti-reflection lenses are lenses which have had an anti-reflective coating applied to them. Anti-reflection coatings are applied to ophthalmic lenses with the purpose of reducing reflections on them. They are deposited as several layers of metal oxides in vacuum coating chambers. As their depth is half the wavelength of visible light, they are extremely thin. Uncoated lenses reflect around 8% of light, while anti-reflection lenses reduce this to as litte as 1%, allowing 99% of light to be transmitted through the lens.

Opticians dispense them because they drastically reduce reflections on lenses, so making them cosmetically superior. They also offer performance benefits because reducing reflections leads to reduced glare, which is particularly noticeable when driving at night or working in front of a computer monitor. It means that wearers often find their eyes are less tired, particularly at the end of the day. Allowing more light to pass through the lens also increases contrast and therefore increases visual acuity.

Many anti-reflection lenses include an additional coating that repels water and grease, making them easier to keep clean. Anti-reflection lenses are particularly suited to high-index lenses, as they tend to have lower light transmission factors.