Anti-Reflection Coating
Preparing Lenses for AR Coating

Inspection and Cleaning

Before being sent to the coating lab, the lenses must be thoroughly cleaned and inspected in your office. A slight blemish or scratch which may go unnoticed on an uncoated lens becomes much more visible once the lens is coated. It�s best to inspect the lenses under a bright light, such as a halogen lamp, to get an idea what the lenses will look like after coating.

The lenses are inspected again by the lab, then thoroughly cleaned with alcohol to remove any markings or dried edger material. In the coating lab, the lenses are subjected to a series of ultrasonic baths which make them �raw� so they can accept a base to which the AR coating can adhere. The lenses are then baked in an oven to remove any excess moisture, since excessive moisture can cause adhesion problems. Finally, the lenses are placed in a vacuum chamber for the coating process where a layer of binding material, either chromium or silicon monoxide, is applied to the lens surface.

Know your lenses. Virtually any lens can be AR coated, including laminates and photochromics. However, AR coating does affect the changeability of photochromics slightly. Lenses should always be coated in pairs to avoid slight variations in residual color.

It�s best to provide the coating lab with ample information about the lenses including, lens material, manufacturer, color, and any in-office treatments you�ve applied including UV dye.

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Tips for Cutting and Edging Lenses that are About to be AR Coated