Eyeglasses/Bifocals
The importance of bifocals in today's society
When and whom the bifocals were invented by
Eyeglasses were invented in the 1700’s. They were invented by Benjamin Franklin. The first pair of eyeglasses were made by hand. Benjamin Franklin invented bifocals, simply because he was tired of switching two pairs of glasses, every time he wanted to see far away or close. He was getting old and was having trouble seeing both up-close and at a distance. As Ben Franklin got older, his eyesight deteriorated even further. Whenever a challenge came up, like any of his inventions, he devised something that would allow him to continue with his favorite hobby- reading. Ben Franklin's new invention called eyeglasses, would become known as bifocals. In 1784, he wrote to his optician and asked him to take the long distance lenses and reading lenses together- simple. Ben Franklin now had the invention that billions use today- Bifocals.
Ben Franklin's invention comes to life
He devised a way to have both types of lenses fit into the frame. The distance lens was placed at the top and the other lens for up close reading was at the bottom of the bifocals. Ben Franklin didn't feel this was enough just to have spectacles. He wanted something he called double spectacles- bifocals. He had taken two lenses sliced them in half and then had the two types of lenses, reading lenses on the bottom and long distance lenses on the top. By solving a big inconvenience, Franklin's invention has helped billions of people lead happier easier lives, as their vision faded with time.
Advantages and Disadvantages of Ben Franklin's invention- Bifocals
The advantages are as follows. His invention allowed a large field of view, in other words it covered your reading capabilities and your long distance viewing as well.
Disadvantages were based on the way they were manufactured back then. Since it was two lenses " stitched" together, they easily got dust within the two lenses, and also the lens itself was heavier. Also, the lenses themselves were held together by something called eye wire, which came apart very easily.
APA REFERENCES
Association, I. H. (n.d.). Benjamin Franklin’s Inventions. Retrieved 11 March 2015, from http://www.ushistory.org/franklin/info/inventions.htm
Eyeglasses and Contact Lenses. (n.d.). Retrieved 11 March 2015, from http://www.stanfordchildrens.org/en/topic/default?id=eyeglasses-and-contact-lenses-90-P02089
Museum of Vision: Exhibitions. (n.d.). Retrieved 11 March 2015, from http://www.museumofvision.org/exhibitions/?key=44
The Origins of Eyeglasses