Evolving Bifocal Glasses to Keep Up With Contacts |

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Evolving Bifocal Glasses to Keep Up With Contacts

By Dog Lover | October 27, 2009

The American gentleman of science, Ben Franklin, who persevered both nearsightedness as well as presbyopia, devised bifocal reading glasses in 1784 to obviate needing to often switch between two sets of eyeglasses.

The original lens pair for correcting astigmia were manufactured by the British astronomer George Airy in the year 1825.

In the history of bifocal reading glasses, the building of pectacle frames also evolved. In early stages oculars were designed to be either held in place with your hand or by maintaining force on the nose. Girolamo Savonarola advised that oculars could be held in place with a ribbon placed over the subject’s head, which in turn was fastened 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 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 produced the Zeiss Punktal spherical point-focus lens system which dominated the eyeglass lens field for many years.

Despite the improving fame of contacts and laser restorative eye surgery, spectacles stay 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 bi focal sunglasses.

Most of these designs are also distinctly better capable of resisting the rigors of everyday wear as well as the occasional accident. Modern frames are likewise frequently contrived from robust, light-weight materials such as titanium alloys that were not available in earlier years.