How long have prescription eyeglasses been around?
From documents that were retrieved in Rome in the 13th Century, we know that prescription eyeglasses were available at that time. They were referred to as "spectacles" rather than glasses. Although we do not know for certain when prescription eyeglasses were invented, we do have proof that they did exist during this time period. A portrait done by an artist named Tomas da Modeno portrays a gentleman wearing eyeglasses. Obviously what we do not know is if they are prescription eyeglasses. There are, however, other documents such as a manuscript written by a man that implies that if the he wasn't wearing spectacles, he would not be able to read or write.
In the 15th century the printing press was invented which meant more reading material was readily available. Thus, the need for prescription glasses increased. The first reading glasses were held by one hand only during the times that they were needed for reading. It was later in the 17th century when people actually wore the glasses regularly, after an optometrist created them with both earpieces. In those times, a person who was having difficulty with their eyesight would just go in and try on several pairs of prescription eyeglasses until they found a fit for their needs. That changed when Dr. FC Donders wrote the first book on examining the eyes to get prescription eyeglasses.
Benjamin Franklin is credited for the invention of the bifocal lens. With a bifocal lens the bottom half is used for reading and the top half is for seeing objects that re further in the distance.
The first lenses in the prescription eyeglasses were made from quartz crystal and very low in quality and durability. Then in the early 1900's, Bausch and Lomb created the glass lens. Today most prescription eyeglasses are made from a plastic material that can be polished and tinted like glass lenses. The advantage to the plastic lens is the lighter weight of the prescription eyeglasses as well as the durability is greatly increased.
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