Once upon a time an eyeglass prescription was almost a punishment. Frame options were few and far between and attractive ones were even harder to find. If you had need for anything more than a minor correction you were doomed to a thick lens that would distort the appearance of your eye and weigh the frames down upon your nose an ears. When you were able to take them off you would be left with sores along the bridge of your nose and possibly at your temples. Who wouldn't dread such a situation.....

Fortuntely recent years have brought greater frame materials which have led to more design choices. New lens materials have allowed opticians to crete lightweight, thin lenses for almost all corrections. Even the old distortion of eye appearance of through glasses has been minimized. Now glasses are a fun fashion accessory that many people embrace.

This change raises the question of why the change, and most importantly what's in a lens?

Perhaps the biggest issue with glasses people used to encounter were thick lenses. We've all heard the term coke bottle glasses or birth control glasses and probably have a vision of someone come to mind. Lenses so thick and shiny you could hardly see their eyes through the glare or if you did they were so magnified they looked like a bug.

Enter modern day and the availability of high index lens materials. High Index Lens materials are in a nutshell thinner and lighter than conventional lens materials. They can be defined as anything having a higher index of refraction than conventional plstic or glass. Without getting too technical, some high index materials can be as much as 50% thinner than conventional plastic lenses. This results in a thinner edge and a lighter lens which makes lighter weight or rimless frame styles an option for most prescriptions.

The only drawback to high index materials is the price. The higher the index of refraction, the higher the price of the lens. Fortunately lesser prescriptions don't really have the need for high index materials. High Index materials aren't always available in every lens design either.

Aspheric designed lenses were introduced in the early 90's. Aspheric design lenses have a complex front surface as opposed to conventional lenses which are spherically designed and oftn end up bulging like a ball. Aspheric lenses offer superior optics as the curve changes as it moves out from the center of the lens. Conventional lens designs have a lot of distortion as your eye travels from the center of the lens because the curve is constant.

Aspheric designed lenses have flatter curves thn conventional lens designs offering a flatter profile and a thinner lens. Becaue of this design feature you can achieve a lighter lens without using a higher index of refraction.

Because the design offers flatter lens, the lens rests closer to our eye. Because it rests more closely to your eye, it results in less distoriton of the appearance of your eye, either magnifying or minifying it.

Once you have a nice thin lens what are the best ways to coat it. With so many options on the market today hre are a few of the most populr it pays to be aware of.

Scratch resistant coating is essential. No lens materials is "scratch proof", not even glass. If you want your lenses to remain scratch free for as long as possible you should make sure your lenses are scratch resistant. Some higher index materials such as poly carbonate have this resistance built in. Other lens materials require a hard coating on either side of the lens to protect it from a drop on the sidewalk, or a simple cleaning with a kleenex.

UV protection is another great option. UV protection is a clear coating that functions in much the same way sunscreen does for our skin. UV protected lenses protect our eyes from dangerous ultra violet rys which are believed to lead to cataracts and other ocular issues. Again, UV protection is an inherent property of poly carbonate so an additional coating is not necessary.

Anti Reflective Coatings are also incredibly popular. Such a coating is both aesthetic and functional. An AR coating reduces glare, reflections and halos around lights making it easier to see when driving at night. It also minimizes internal relfections on a lens so thy appear thinner and your eyes appear crisp and clear. A/R coatings can be difficult to clean.

Mirror coatings are a final coating option for lenses. They are available in a variety of colors that are strictly aesthetic. The wearer of the lenses perceives no difference in color while wearing such a coating. They offer a highly rflective surface making it very difficualt to see the wearers eyes.

Given the various options available to eyeglass wearers today aesthetic possibilities are endless. Thick lenses can now be thin, shiny lenses are now nearly invisible, round bulgy lenses can now appear flat. When shopping for eyeglasses keep these options in mind enabling yourself to choose the perfect pair. What's in a lens? Everything!