Prior to the 1930s, eyeglasses were only available without any kind of coating. Developments since then have allowed multiple coating types to be added to a single lens. This allows for clarity and lens longevity that were previously impossible, giving those who wear eyeglasses the freedom to purchase the best possible pair of eye wear for their needs.
Definition of Multicoating
As processes developed to allow multicoating, the available varieties of eyeglass lenses increased. Lenses today can be uncoated, fully coated (FC), multicoated (MC) or fully multicoated (FMC). Uncoated lenses involve no extra coating on the surface, while FC lenses come with one full coating. MC lenses have multiple types of coating and come in a variety of combinations. FMC lenses are basically MC lenses with all coating layers dispersed across the entire lens.
Types of Coatings
The types of coatings with which eyeglasses can be treated vary depending on the type of material from which the lenses are made. The most common options include anti-reflective coating, scratch-resistant coating, anti-fog coating and ultraviolet (UV) treatments. Anti-reflective coatings eliminate glare and can improve the wearer's vision at night. Scratch-resistant coatings drastically reduce scratches to the lens over time, while anti-fog coatings prevent lenses from fogging up. UV treatments block all UV rays from passing through the lens.
Benefits of Multicoated Glasses
In addition to the specific benefits different coatings offer, multicoated lenses also allow more light to pass through them than other types. An uncoated lens can lose up to four percent in light transmission, due to scattering and reflections. A fully coated lens drops that loss to 1.5 percent, but multicoated lenses lose only .25 percent in light transmission. While these numbers may seem negligible, the corresponding reduction of glare for those who wear eyeglasses is significant.
Summary
Multicoated lenses are a great option for eyeglass wearers who want more out of their glasses. Multicoated eyeglasses are useful for children, who may need scratch-resistant and anti-reflective coatings, as well as UV treatments. Multicoated lenses are the most functional of eyeglass lenses and present the least intrusive option for those who value comfort.