Bifocal History
March 1, 2009 by Stacy42
The American man of science, Benjamin Franklin, who endured both nearsightedness as well as presbyopia, devised bifocals in 1784 to obviate having to frequently alternate between 2 pairs of glasses.
Who knew that several centuries later Franklin’s invention would lead to the ideal computer glasses with the development of the occupational bifocal lenses.
The 1st lenses for rectifying astigmia were manufactured by the British astronomer George Airy within 1825.
Across time, the building of spectacle frames also developed. Early on oculars were contrived to be either held in place with hand or by maintaining force on the nose. Girolamo Savonarola advised that oculars could be held in place with a ribbon passed over the subject’s head, this in turn fastened by the weight of a hat.
The contemporary fashion of bifocal 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. The history of bifocal reading glasses is more you might assume, actually.
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 several years.
Despite the improving fame of contacts and laser restorative eye surgery, spectacles stay quite 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.
Either of these designs offers distinctly better ability to resist the stresses of day-to-day wear as well as the occasional accident. Contemporary frames are likewise frequently made from substantial, light-weight materials like titanium alloys that weren’t available in earlier times.
Melissa, I understand the choice of name can come from some meaning, but in the real world that meaning is of little consequence to what happens to you in life, unless your name doesn’t sound Caucasian, there is economic reports that prove that at least for the US. Personally, I think names are stupid, and I don’t care if people call me Dick Trough.
Thanks for posting, friends! It’s just amazing to think what could be done with this technology if advanced.
I agree there isn't that much positive writing about Essilor on this site but if there was more than usual, I'd think it was run by Essilor. I think they understand that this is what comes with being the biggest lens maker and lab holder in the world. I wonder much say they have in their partner labs? I use a lab that was recently bought into by Essilor but I haven't asked if anything has changed. Anybody have any thoughts?
I started to use more Varilux after reading some of the stories n this site. I had to research for myself and so far my change from Hoya products has been successful. For the record I use the Comfort 360 and Definity short solely unless specifically requested by my customers. I wish the turn-around was quicker but I wouldn't be doing this if it hadn't been for stories here.
I just had a Zeiss rep in here and I said I'd look into them once Eyeoverheard started bashing them.
Thank you, Happy Thanksgiving and keep us laughing.
It sounds pretty good X]]]
Keep writing