The invention of the bifocals was one of the most important inventions of the 1700s. They have changed the lives of both children and adults that have issues with their eyesight. They rid people of eyestrain and headaches. Also, bifocals rid people of the inconvenience caused by having to shift from one pair of glasses to the other. Bifocals also allowed for more types of glasses to be developed.
As Benjamin Franklin grew older, his vision worsened. He became both far-sighted and near-sighted and the constant switching of his glasses frustrated him so much that he decided to solve this problem. He invented a pair of glasses that incorporated both lenses into one frame called bifocals. “Bifocals are a type of prescription eyeglasses designed for people who need both near and farsighted vision correction. Benjamin Franklin developed the first pair of bifocals in August 1784” (Beam "What Are Bifocals?"). With these two-lense bifocals one could look through the upper half to see far away and the lower half for seeing closer things. Many historians question who invented the bifocals although, due to letters written by Benjamin Franklin to his friend George Whatley, it is a known fact that Franklin was indeed the true inventor of the bifocals (The Electric Franklin "Benjamin Franklin's Inventions").
They are generally used by people over forty years old (Heiting "Bifocals and Trifocals for Vision Over 40"). Single vision glasses and bifocals are very different types of glasses because they only help people with nearsightedness. This is why bifocals are very useful because they are two pairs of lenses within one frame. Bifocals are generally associated with adults, but there are many cases in which children too require bifo...
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...and vision care, 1 Jan. 2014. Web. 23 May 2014. .
Heiting, Gary, and Mark Mattison-Shupnick. "Bifocals and Trifocals for Vision Over 40." All About Vision. All About Vision, 1 Jan. 2014. Web. 23 May 2014. .
The Electric Franklin. "Benjamin Franklin's Inventions." Ushistory.org. Independence Hall Association, 4 July 1995. Web. 23 May 2014.
"Trifocal Glasses Lenses,."Trifocal Lenses,. Eyeglass Lens Direct, 1 Jan. 2014. Web. 23 May 2014. .
Twin Cities. "It's The Little Things." PBS. PBS, 1 Jan. 2002. Web. 23 May 2014. .
"welcome to forcaza." welcome to forcaza. N.p., n.d. Web. 23 May 2014. .
What new Thomas Edison invention fools Fievel into thinking he has found his Papa? What year was it invented? (4 pts)
Seltzer, Jo. "Ophthalmologists Express Skepticism About Vision Therapy." Stlbeacon.org. N.p., 30 Nov. 2010. Web. 1 Mar. 2014.
My interest in the career of optometry stems from my first experience in the optometry office to receive my first pair of glasses when I was in middle school. I distinctly remember the moment when my optometrist slipped my new glasses over my eyes for the first time. Suddenly, everything in the room came into sharp, clear focus. I knew that the glasses would help me see the board in school, but I was astonished to find that I could see small details about the room, as it had never before occurred to me that I should have been able to see these details. I was also surprised that I was even able to see the expressions on the faces of people who were standing far away from me. It was one of the most incredible, freeing, and empowering moments of my life. As I walked out of the optometry office, I felt
Although hard times were many in the need for a strong new nation for the people, many of the prominent leaders still pursued inventions that benefited themselves and the people. In 1784, Benjamin Franklin developed bifocal glasses. He w...
... and make a conclusion. Ben’s goal was to conduct electricity and extract an electrical charge. Once the storm came, he attached a key to a kite and flew it in the air, after the first strike on his key, Ben was then aware that lightning is indeed a form of electricity. After this, Ben then began to devise many different types of lighting rods. Today, Benjamin Franklin's lightning rods could soon be seen on top of many buildings and homes serving to protect from dangerous lightning strikes.
In 2010 there were 53.8 million searches about eyeglasses, 70.9 million searches about sunglasses. Customers who bought eyeglasses online were satisfied 90.4%. (48.1% excellent, 42.3% good).
Jones, R.V. "Benjamin Franklin." Notes and Records of the Royal Society of London . no. 2 (1977): 201-225. http://www.jstor.org.ezproxy.lib.usf.edu/stable/531827 (accessed November 21, 2013).
Benjamin Franklin is known for conducting lots of experiments dealing with electricity. His most famous being the kite experiment. He became fascinated with electricity when he was accidently shocked in 1746. Benjamin wondered if there was a way to protect buildings and the people inside of them from lightning. He thought that this could benefit people in the
The Oyez Project. N.p., n.d. Web. The Web. The Web. 18 Mar. 2010. http://www.eyes.org/cases/1970-1979/1971/1971_70_18>.
Web. The Web. The Web. 21 Feb. 2014. Buckman, Adam. A.S. & Co.
From a young age, he was extremely smart. His intelligence is shown in his many inventions such as his experiment in electricity. One of Franklins greatest electricity experiment was the kite. The kite was made out of two strips of cedar which reached to the corners of a thin handkerchief. The kite was raised with a tail, loop and a string with a sharp pointed wire, rising a foot above the wood. When thunder clouds come over the kite, the wire will draw electric fire from the kite. Franklin found pleasure in science and wanted to educate his citizens as well as himself on electricity Another great invention that Franklin created was the lightening rod. The lightening rod was a small rod, about three to four feet which stuck out of the ground and the other side was about six to eight feet, which would be placed on the highest part of the building. When the lightening hit the rod, it would be conducted to the ground through the wire which would prevent a fire and create electricity. Through these inventions, it is shown how Benjamin Franklin proved his greatness by tampering with electricity which can be a very difficult thing to
• Kibilko, John. “How Much Does It Cost for the Education & Skills to Be a Pediatric Neurologist?” eHow.com. 1999-2014. Web. January 6, 2014.
N.p., 12 Sep 2014. Web. The Web. The Web. 10 Sept 2015.
Meece, Mickey. "Lenses to ease the strain from staring at screens." New York Times 15 Mar. 2012: B9(L). Opposing Viewpoints in Context. Web. 19 Mar. 2014.