Eyeglasses are corrective instruments that are worn on the face to correct deficiencies or lacking areas of a person’s vision. They can also be worn for eye protection or pure style, depending on the preference of the wearer. Eyeglasses are innovative instruments that have changed very little since their invention and adaptation in the late 1700s.
Contrary to popular belief, the creation of eyeglasses actually dates back long before Benjamin Franklin’s adaptation of them in the 1700s. Earliest versions of eyeglasses were made in Italy as early as 1000 A.D. with quartz lenses set into bone, leather or metal frames or monocles. These glasses were purely used for magnification, however.
Population and Eyeglasses
According to Earth 911, roughly 25 percent of the world’s population requires eyeglasses in some form.
Supply and Demand
Earth 911 also states that more than 1 billion people in the world require eyeglasses, but cannot afford or find them.
More than 50 percent of the residents in African institutions for the blind would be able to read large print with proper eye glasses.
Earth 911 states that an average pair of eyeglasses in Africa can be priced at more than three months' normal salary for an average African.
Modern glasses are usually made from plastics rather than glass to prevent cracking and damage to the eyes in the event of an accident. The plastics used are often resistant to cracking or breaking and sooner snap than shatter. Plastic also is lighter than glass.
According to Earth 911, more than 4 million pairs of standard reading glasses are thrown away every year in North America.
Eyeglasses inspired the creation of contemporary contact lenses in 1949, which before that had been a dangerous experiment practiced by scientists in Germany, Italy and France. Eventually, this would lead to corrective laser eye surgery, developed and commonly used in 1991.
Eyeglasses went through many different stages of evolution ranging from the creation of bifocals, trifocals, fused bifocals, and other multifocal lenses, all of which are still used today.
Most plastics used for eyeglasses today are coated with certain chemicals that make them resistant to scratching, water damage and glare.