What Are Glasses Made Of?
“Letters, however small and indistinct, are seen enlarged and more clearly through a globe or glass filled with water.”
History Of Glasses
This simple sentence, written by Seneca the Younger in the 1st century AD, is how eyeglasses first got their start. Though this was the first recorded acclamation of magnified sight, the thorough history of eyeglasses trails consistently through the ages.
The first legitimate pair of eyeglasses is believed to have been created in Italy around 1286, though Marco Polo claimed to have seen many a pair in China in 1275. The invention, which many considered a form of art, made for good vision and quickly spread in popularity.
Benjamin Franklin, an American scientist, is considered the inventor of bifocals. After suffering for years with myopia (nearsightedness) and presbyopia (inability to focus on close objects) Franklin constructed the two-lens-in-one concept that allowed for individuals to see both near and far with the same pair of spectacles.
Perhaps one of the biggest evolutions in the history of eyeglasses is the frame and structure in which they are created. Early eyepieces were either hand-held or rested on the bridge of the nose (with hand support). It wasn’t until 1727 that the modern style of glasses was invented. However, the public didn’t immediately accept the design that passed over the temples and secured behind the ears and it wasn’t until the 19th century that the modern form of glasses became popular.
What Are Eyeglasses Made Of?
This may seem like a foolish question: glasses are made of glass, right? Not entirely. Most lenses on both eyeglasses and sunglasses are made from one of three materials.
1) CR-38: This is an incredibly durable plastic
2) Polycarbonate: Like the CR-38, this plastic is incredibly durable. It’s so durable, in fact, that it’s shatter-resistant.
3) Glass: Though not as popular as the previous two, glass is still used as a reliable material for glasses, especially if the eyesight is abnormally poor.
The lens material is just one of many important aspects of glasses. When shopping for glasses, be sure to consider the following:
Also known as the “legs,” “stems” or “ear pieces” of the glasses, this is essential when keeping the glasses on your face. Below are four commonly used materials:
1) Zyl: A medium-grade plastic
2) Optyl: A high-grade plastic-nylon
3) Titanium: A strong, lightweight metal
4) Steel Alloy: A heavy metal combination
Though the plastic temple materials are frequently used because of their sturdiness, a titanium design would be the best choice for lightweight, easily adjustable glasses.
Hinges are important in the design of glasses because they connect the temples or “legs” to the actual frame. They also help to make the glasses more compact when not in use. Despite which material is used in the construction of the temples and frames, hinges are comprised of two parts that are typically made from high-quality steel alloy. These two parts are connected by a common screw (also steel alloy) and help to open and close the temples.
The frame, which is responsible for holding the lenses, can come in a variety of different materials. Affordable materials like plastic and steel alloy frames are reliable and frequently used, where as materials like gold, platinum, ivory and even wood are much more pricey and can be difficult to find.
Frames with built-in nosepieces are typically made from the same material as the actual frame, and can be challenging to adjust and fix. Frames with adjoining nose pieces, on the other hand, are made from plastic and/or rubber and tend to be more “user friendly.”
Most vision insurance plans help to cover the cost of receiving and maintaining glasses and you should further discuss getting glasses with your vision insurance provider. VSP Direct knows the difference a pair of glasses can make. With routine eye exams, excellent glasses and contactcoverage and a staff of friendly, helpful representatives, VSP Direct helps you navigate the process of getting glasses.