The American gentleman of scientific discipline, Benjamin Franklin, who endured both myopia as well as presbyopia, devised bifocal reading glasses in 1784 to avoid having to frequently switch betwixt two frames of eyeglasses.
The original lens pair intended for repairing astigmia were manufactured by the British astronomy expert George Airy within the year 1825.
In the history of benjamin franklin bifocals, the building of pectacle frames also evolved. In early stages glasses were designed to be either kept in place with your hand or by maintaining force on the bridge of the nose. Girolamo Savonarola noted that eyeglass lenses could be held in place with a ribbon passed over the subject’s head, which in turn was fastened by the weight of one’s hat.
During recent bifocal history, the contemporary fashion of bi-focal reading glasses supported by temples passing over the ears, was produced in 1727 by the British lens maker Edward Scarlett. These designs were not at once prosperous, however, and assorted styles with attached handles like « scissors-glasses » and lorgnettes stayed fashionable throughout the eighteenth and into the early nineteenth century.
In the early twentieth century, Moritz von Rohr at Zeiss made the Zeiss Punktal spherical point-focus lens system which controlled the eyeglass lens field for many years.
Despite the rising fame of contacts and laser restorative eye surgery, eyeglasses remain rather common, as their technology has continued to evolve. For example, it’s currently possible to buy frames constituted of special memory metal alloys that return to their correct configuration after being bent. Other frames have spring-loaded hinges.
Glasses have come a long way, haven’t they? In fact, today you can even buy rimless eyeglasses.
Many of these modern contraptions are also distinctly better able to resist the rigors of day-to-day wear and tear and the occasional accident. Contemporary frames are also frequently made from solid, light-weight materials like titanium alloys which weren’t obtainable in earlier times.
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