Sunglasses and Eyeglasses Sizing Chart and FAQ
Glasses frames have three basic measurements: the eye, bridge, and temple.
The eye size refers to the horizontal width in millimeters of one of the frames lenses. The measurement is taken from the inside of one side of the frame to the inside of the other side of the frame. The lens is measured from its furthest point, where it would intersect with a vertical line.
The bridge measurement is the distance in millimeters between the two lenses. It is measured between the two closest points of the two lenses.
The temple length is measured along the length of the temple, from one end to the other, including the bend. Many frames are constructed with an endpiece that extends from the frame front back along the line of the temple. This backward extension of the frames endpiece could be as little as 2mm, or as much as 15mm. When the endpiece extends further back, the temple length tends to be smaller to compensate. As a result, if you are accustomed to a 145mm temple length, a 135mm temple could work perfectly for you if your new frame has an endpiece that extends back 10mm. This is also the case with many sunglasses with a wrap design. The wrap has the effect of bringing the frame front back towards the ears, thereby requiring shorter temples lengths to compensate.
Acetate: A thermoplastic resin composed of plasticized and stabilized cellulose acetate; this means it can be repeatedly softened and reformed under the action of heat and pressure, and yet still reinforce when it is cooled.
Propionate: An organic thermoplastic material based on cellulose whose features are very similar to acetate. It is injected into a steel mold a very high temperatures.
Metals usually start with a base metal that is either a copper or nickel alloy, then is plated with a fine metal, such as gold, to give them a rich finish.
Monel and Nickel Silver: Offer a good machinability and excellent elasticity.
Bronze: Metal alloy with a strong tendency to work-harden during the cold pressing phase; as a result, bronze has outstanding elasticity and shape retention mechanical features.
Stainless steel: Lightweight, comfortable, high elasticity.
Titanium: Pure material whose unique features, such as mechanical and corrosion resistance, allow the designing of particularly sturdy, lightweight and non-allergic frames.