Bifocal Reading Glasses and Their Technological Development
The United States man of science, Ben Franklin, who persevered both nearsightedness as well as presbyopia, invented bifocals in 1784 to avoid needing to frequently alternate betwixt 2 frames of glasses.
The original lenses for correcting astigmia were constructed by the British stargazer George Airy in 1825.
Along the history of reading bifocals, the development of eyeglass frames also progressed. Early on glasses were contrived to be either kept in place with your hand or by maintaining force on the nose. Girolamo Savonarola advised that eyeglass lenses could be held in place with a ribbon passed over a person’s head, which in turn was held secure by the weight of one’s hat.
Entering modern 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 creator Edward Scarlett. These designs were not at once prosperous, however, and assorted styles with attached handles like “scissors-glasses” and lorgnettes remained fashionable throughout the eighteenth and into the early nineteenth century.
In the early 20th century, Moritz von Rohr at Zeiss made the Zeiss Punktal spherical point-focus lens system which dominated the eyeglass lens domain for many years.
Despite the rising fame of contacts and laser restorative eye surgery, eyeglasses remain rather common, as their engineering has continued to improve. 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 bifocal glasses.
Many of these modern contraptions are also distinctly better able to resist the challenges of day-to-day wear as well as the occasional accident. Contemporary frames are likewise ofttimes made from solid, light-weight materials such as titanium alloys which were not available in earlier days.
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