Specialty Lenses
Specialty Lens Coatings

 

Specialty Lens Coatings

Anti-reflective Coatings
Ultraviolet Coatings
Scratch-resistant Coatings

Normal lenses have surface reflections because light transmission through the lens is only about 94%(all thin lenses are more reflective and transmit only about 90%). Loss of the remaining 6% - 10%occurs as light bounces off the front and back surfaces. We are familiar with this when we remember looking at our reflection of ourselves in a window, especially when it is dark outside. This is also why we can see our eyes or cheeks in the backside of glasses lenses. Until recently the only thing to do about these reflections was to try and adjust the frames to redirect the bounce-back of light, change the curve of the lens or even change the prescription. Very little helped.

What changed for the best was the introduction of anti-reflective coatings. AR is a series of multi-layers of metallic oxides that when applied to the surface of lenses eliminates reflections by increasing the transmission of light to almost 99.5%. With this coating lenses are almost completely transparent which helps with not only improving the cosmetics of glasses (how we are seen in glasses with reflections) but also the way we see through the lenses. No more seeing our eyes and cheeks on the inside of the lenses, no more seeing ghost images and shadows of lights and no more multiple images of oncoming headlights while driving at night. One of the reasons contact lens wearers like the way they see through them is because there are no reflections getting in the way of their view of the world. AR coated lenses rival the transparency of contacts. This is probably the most important introduction in the world of glasses since the arrival of plastic lens materials.

Because light transmission is now so high, anything interfering with the surface shows up on the lenses. Dust, smudges and fingerprints will be more noticeable. The way to keep lenses clean is simple. Just wash them with a mild soap and warm water and dry them with a soft cotton cloth. The best soap is liquid dish soap or shampoo. These cut grease without leaving any film and will not harm the lens or coating. We also supply micro-fiber cleaning cloths that are great when the lenses get smudged and you are not around any water. With the cloth lightly wipe the front and back surface of the lens to first remove any dust or grit. Then after shaking the cloth to remove the debris rub the lenses to remove the fingerprints or smudges. The cloths should be washed to prevent the buildup of skin oils and dust.

 

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