Anti-Reflection Coating
Overview of AR Coating

The most obvious and demonstrable advantage in the use of an AR coating is its visual and cosmetic improvement qualities. AR coating reduces reflections off the front and back surfaces of the lens that allow many people to actually see better, especially at night.

Anti-reflective coatings have been popular for many years in Europe and Asia because of the visual and cosmetic improvements to the wearer. It is estimated that only about 12�15 percent of optical prescriptions in the United States are coated with AR, compared with 65 percent in Europe and 95 percent in Japan. Part of the reason for the relatively low acceptance in the United States is the popularity of plastic lenses; it is more difficult to reduce reflections on plastic lenses than it is on glass. While anti-reflective coatings have obtained a reputation as being difficult to clean and easy to scratch, recent improvements in coating and lens technology have begun to overcome these earlier objections resulting in a more viable product.

It was in 1892 when the principle of �thin film coating� was first discovered. Dennis Taylor, an English scientist, found that an older lens that had been oxidized would transmit more light than a newer lens. The cause of this phenomena was tarnish which had, with time, accumulated on the lens through oxidation. Taylor accidentally discovered that the tarnish caused improved light transmittance through the lens. By 1904, Taylor patented a method for artificially aging lenses by using a method of chemical treatment.

Forty-three years later modern AR coatings were developed in Germany, but were held by the government for military reasons until 1939. The first introduction for ophthalmic purposes didn�t come until 1957 for the glass market and 1974 for plastic ophthalmic lenses. This early introduction was in Europe only.