subject: The History Of Glasses [print this page] Glasses can be traced back in our history as far as the thirteenth century. The first signs of glasses lenses were found in elementary crystals or convex shaped glass that have been found in archeological digs dating back several thousand years. It is believed however that these shaped "lenses" were not used for any eyesight correction of glasses lenses, rather they were used most probably as magnifiers. It wasn't until much later, likely the first glasses as such were developed in the mid-thirteenth century from convex lenses. The term lenses itself is most likely derived from the latin for "bean" as the slightly convex shapr of the bean resembles a basic lens for spectacles.
The earliest lenses used in any sort of glasses known were made of quartz crystals and could be used for correction of vision as well as simply magnifying.
As their viability as glasses became more widely known and so popular, the process to make the glasses lenses developed first into spectacles made from hand blown glass - and later (likely the very end of the thirteenth century) into shaped glasses whereby molten glass was formed into a convex mold and so defined a lens that could be used as glasses or spectacles for correction.
It is also believed that some Roman Emperors had lenses formed into a type of spectacles that were made of emeralds, and so became what were probably the first prescription sunglasses.
The real development of glasses as documented however was in Italy and were produced by craftsmen who were used to making jewelry and so able to incorporate small crystal lenses into structure that could support them in front of the eyes without having to be held.
Of course this made the earliest glasses extremely expensive as they were handmade by artisans and used glass which was a very expensive material in the 14th and 15th centuries. The first actual documented wearer of glasses however was the Bishop da Provena in the 13th century who had some simple magnifying crystals connected to short handles and then joined together so that they could be balanced on his nose.and became at the same time the first example of "pincenez".
There remains today some dispute about the origins of glasses and spectacles, as there is some evidence that Marco Polo encountered them when exploring the East and landing in China in 1270 or 1271. There is further credit give then by the Chinese themselves to the even earlier development of glasses - or at least of a practical corrective (non-magnifying) lens to Arabia as much as a century earlier.
Despite this somewhat disputed provenance, there is no doubt as to the popularity that glasses enjoyed as the manufacture of them became less of an artisan skill and more of a manufacturing process using glass and being predictive of the lens curvature and so correction for myopia in particular.
It is interesting to note that although there is good documentary evidence of glasses being produced in some fairly significant volume in the 16th century - it was not until much later in the early part of the seventeenth century that the physics of the lens was actually understood and how the correction for myopia actually came about. This discovery or explanation is credited to Johannes Kepler who studied optics for several decades, eventually publishing his work in 1604.
