No one knows for certain when eyeglasses were invented, although documents from the 13th century prove the existence of eyeglasses at that time. Several sources quote a manuscript written in Rome in 1289 by a member of the Popozo family that says, "I am so debilitated by age that without the glasses known as spectacles, I would no longer be able to read or write." A painting done by Tommaso da Modena in 1352 includes the first known artistic representation of eyeglasses.
Historians credit the Chinese with carving the first frames more than 2,000 years ago, but apparently those frames did not contain lenses and were used to protect their eyes from "evil forces." The frames were carved from tortoise shell, a sacred material.
The use of a magnifying glass was first recorded in about 1000 A.D. It was called a reading stone and was placed on top of reading material to magnify letters. Monks used it to copy manuscripts. Later, Venetian glassblowers constructed lenses that could be held in a frame in front of the eyes. Glasses for distance vision first appeared around the middle of the 15th century, and there are various references in literature of that time to spectacles for "distant vision."
In the 15th century, the printing press was invented, making reading materials more available to the public and increasing the need for glasses. Early eyeglasses were held by hand in front of the eyes or designed to "perch" on the nose. It wasn't until the 17th century that a London optician perfected the use of side pieces that rested on the ears.
In 1784, Benjamin Franklin invented a bifocal lens with the top half for viewing at distance and the bottom half for reading. (from VisionRX)