Eyeglasses used to be called spectacles. Originally, the inventor, Salvino D'Arminte, used two spheres of glass that he inserted into a hinged holder. This contraption resembled two magnifying glasses held together by the hinge, and allowed wearers to place the eyeglasses on the bridge of their noses by forming a "V" with the two handles. By all accounts, D'Arminte's breakthrough in 1284 was the first pair of wearable eyeglasses. Before that, people used a reading stone, a lump of glass that they placed on top of written material. The stone magnified the type and made it easier to see.
Although D'Arminte has received credit for the invention of wearable eyeglasses, they first appeared in artwork by Tommaso da Modena. His frescoes depicted monks wearing round spectacles as early as 1352, in some sketches. Other artists also painted works with subjects wearing spectacles or using eyepieces, like monocles.
Eyeglass designers originally used quartz for the first lenses in eyeglasses. Optical glass was a major leap forward. It made it possible to match a lens prescription to vision problems. Pope Leo X was the first person in recorded history who wore concave lenses. These were invented in the 16th century for nearsighted people who needed help seeing things at a distance. A convex lens corrects farsightedness, difficulty seeing up close.
The next eyeglass development was sunglasses. Roman history records show that the emperor, Nero, used an emerald to shield his eyes against strong sunlight while observing athletic competitions. However, the technical knowledge to produce sunglasses did not arrive until the 18th century. In 1752, an eyeglass designer, James Ayscough, created blue and green lenses for eyeglasses. He felt that white light damaged the eyes. These sunglasses were designed as corrective prescription eyeglasses.
Benjamin Franklin moved the science of vision correction forward when he invented bifocal lenses in 1784. As people age, some have difficulty reading printed words. Franklin's idea was that with bifocal lenses, people who needed eyeglasses to see things at a distance clearly would benefit from having a way to view reading matter, up close, using the same pair of eyeglasses. Franklin's bifocal eyeglasses had two separate pieces of glass in the same frame. A hundred years passed before the one-piece bifocal lens was invented. Consumers can now purchase bifocal glasses with or without the telltale line that separates the two types of corrective lenses in their frame.
Eyeglasses have always been hard to sell to children and adults alike. People who needed them usually put off buying them until they had no other choice. Even then, most children would only wear their eyeglasses when they were not in the public eye. Until designer frames entered the market, eyeglasses were often unflattering. Now some fashion designers, like (Calvin Klein), offer such attractive frame styles that people who don't need eyeglasses daily buy prescription eyewear. Good quality eyeglasses in a stylish frame can be quite an investment. Many consumers turn to online and discount opticians to reduce the costs of filling the prescription for their glasses.