Photochromatic lenses are becoming more and more popular for many people. Here's a little primer on what photochromatic lenses are, what they do, how they work and their uses:

What are Photochromatic Lenses?

Photochromatic lenses are glass or plastic lenses that have a layer of molecules inside of them that reacts to UV rays. When a person wearing photochromatic lenses walks from a hotel onto a sunny beach, the lenses will detect the UV rays and will automatically darken to protect the eyes from the UV rays. After just a few minutes in the sun, the lenses should darken to the point that the UV rays are completely blocked from the lens wearer's eye. Photochromatic lenses were first developed in the 1960's by the Corning company, however, the lenses did not become widely available until the 1980's when the American Optical Corporation sold the lenses under the PhotoLite name. The most popular brand of photochromatic lenses available today is the Transitions line.

How They Work

The materials that produce this effect are usually silver chloride in the form of microcrystals. These crystals react to UV rays by progressively darkening the lens in response to the amount of UV rays that it encounters.

Advantages

There are many advantages to photochromatic lenses, including medical advantages for people with light sensitive eyes, advantages for convenience and work issues, benefits for older people who don't want to carry additional glasses, benefits for people in certain industries where changing their glasses constantly would create a distraction as well as many other advantages and benefits for people in many industries, services and regions where weather is constantly changing.

Who Should Use Them

Photochromatic lenses are great for anyone to use. Whether on the slopes, driving, around town, the beach, on vacation, just about anywhere, this technology will come in handy. Also, anyone with low vision, elderly people, people with sensitive eyes, people who work in a setting where they are exposed off and on to sun and anyone looking for the convenience of not having to change their prescription glasses to sunglasses and vice versa every time they go outside will certainly find them useful. People with eye problems would gain great benefits from wearing prescription glasses with photochromatic lenses because doctors can adjust the colors of the lenses to enhance vision for patients with specific ocular problems. People with extreme eye sensitivity, especially those with eye diseases can also benefit from these lenses, since the color can be adjusted to significantly lessen stress on the eyes. For instance, a patient with a moderate eye sensitivity could benefit from lenses that darken to a reddish/brown to protect the eyes and blunt anything especially bright. Photochromatic lenses are now being offered in ski and snowboarding and sport goggles and glasses and these are excellent applications that will take advantage of them, especially for people with prescription glasses.