Overview Of Spectacles
Eyeglasses have become such an integral part of our lives that we do not even stop to think twice when we see someone wearing a pair of glasses. But at one point of time, it was an innovation that revolutionised the way one looked at things. Literally.
Originally, glass has always been the material of choice for any kind of vision corrective glasses or magnifiers. Glass, however, is dangerous, heavy, expensive and hard to shape. So the use of plastic and polycarbonate in making the lenses became widespread. One of the most popular material used today is Columbian Resin verson 39, also known as CR-39, as it is the most convenient material for lenses with an index of 1.5.
In the beginning, there were no frames attached to the eyeglasses. Instead they would be held up on a handle. When the frame was put on the glasses, they were made of bone, wood, metal or leather. In the 1900s, tortoiseshell and horn-rimmed glasses were popular. It was not unknown for rich people to have had eyeglasses made of gold or silver frames. Today, as with the lenses and many other things, the most common material used for the frame are plastics and metals.
ORIGINS & HISTORY
Though some kind of vision correction have existed in many cultures around the world for many years, they were more usually magnifying glasses or sun-protection glasses, rather than vision corrective glasses. Ancient Egyptians, Indians, Romans and Chinese all experimented with glass. The invention of eyeglasses is normally attributed to Venetians, who invented the reading stone. Although the Venetians also started off with inventing a magnifying glass to enable people with poor eyesight to read, they quickly learned to use it for vision correction as well. The original magnifying glasses were called reading stones.
The history of eyeglasses is not recorded very well, so what we do know comes from recorded sources. There may have been other civilisations that had invented crude aids to sight but no records exist now.
The earliest we have records of the invention of eyeglasses was recorded by a couple of Italian monks from the St Catherine’s Monastery, Giordano da Rivalto and Alessandro della Spina. Giordano mentioned in a sermon he gave in 1306 that it was less than twenty years ago that glasses for better vision were invented. From this, we can deduce that the first vision correction glass was probably made around 1286 in Italy. The monk Spina was so taken with these newfangled contraptions that he started making them and distributing them, thus spreading the gift of eyesight.
Eyeglasses had become common enough by 1300 for the Venetian guild to start issuing regulations on its manufacture and marketing.
The Egyptian scientist, Alhazen, had done extensive research on eye correction technologies in the late 900s and early 1000s. Known as the Father of Modern Optics, it is conceivable that the original inventor of the eyeglasses used his work and developed it further.
One of the biggest myths surrounding the invention of eyeglasses is that it was invented by a certain Salvino d’Armate from Florence. There is not much information on why such a tale came into existence, but it has now been conclusively proved that d’Armate was not responsible for the invention of eyeglasses.
In the fifteenth and sixteenth centuries, the first frames were created in Spain. Silken threads were attached to these frames and looped over the ears. It was around this time that the eyeglasses were imported to the East, and Chinese improvised on the frames.
In the late 1700s, Benjamin Frankin developed bifocals, which is used for correcting both long and short vision problems with one set of glasses. Lenses for correcting blurred vision or astigmatism was invented in England in 1825 by George Airy, an astronomer. At one point in the 1800s, glasses such as monocles were used as fashion statements rather than from any real need. John Bosch invented the fused bifocals in the early 1900s, making it more convenient for people with both near and far vision problems. After this period, there were rapid advances in the development of technology, the invention of contact lenses, and so on.
Today, there are glasses to correct almost all kinds of eye problems. But the research and development of new technologies continue, because sight, after all, is one of the most important of the five senses.