The Invention of Different Types of Glasses: Bifocals
by Lillian Bonar
Essay: The Invention of Different Types of Glasses: Bifocals
Pages: 11
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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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