You probably do not give your glasses much thought unless you cannot find them, they are broken or need to be replaced, or the lenses are dirty. Whether you think about them much or not, your eyeglasses can become part of your face, and the lenses and frames have distinctive features. There are four basic parts of eyeglasses, and each part has a specific function.
Your lenses are the part of your eyeglasses that correct your vision. The lenses are either convex or concave. Convex lenses correct farsightedness and convex lenses correct nearsightedness.
Lenses are made from plastic, polycarbonate or glass. Plastic is the most popular material, glass is the heaviest and polycarbonate is the most shatter-resistant and lightweight.
Lenses are either single-vision or multi-focal. Single vision lenses correct just one type of vision problem; multi-focal lenses help with distance and near vision problems.
Your frame front, or chassis, is the part that holds your lenses. The frame front as well as the rest of the frame is made from either plastic or metal. Plastic frames are usually made from zyl, cellulose acetate propionate or blended nylon. Metal frames are constructed from a material called monel (a combination of various kinds of metals) or from titanium, beryllium, stainless steel, flexon and aluminum. The frame front is the biggest part of your eyeglasses.
Frame temples, also called "arms," connect to the front of your frame and rest on your ears. Most temples are straight with a slight bend. However, some frames have cable temples that are more curved and wrap behind and under the ear.
Nose Pads and Bridge
The bridge of your frame is the part that rests on your nose. A solid bridge is a U-shaped form that is either part of the chassis or removable on certain metal frame styles. Some frames have adjustable nose pads that are moved to fit the angle of your nose, called the splay angle.