by Frank Drummond

Sometimes known as readers or cheaters (as hipsters called them), reading glasses help change the focal length of the eye to alleviate myopia, hyperopia, or astigmatism. There's much debate on the year glasses were invented but by most accounts, they were in use in China in the 12th century. Wide use of reading glasses weren't reported in Europe until the late 13th century. Ben Franklin invented bifocal lenses in 1784 to prevent him from having to switch glasses. George Airy invented astigmatism glasses in 1827.

Diopters are the unit of measurement used for the power of a lens. Over the counter reading glasses are usually in the +1 to +3 diopter range. The diopter range for those with nearsightedness (myopia) will always be in the negative range. Prescription lenses are those that are prescribed to an individual by an ophthalmologist or optometrist. They're designed to conform to a specific level of myopia or hyperopia.

The only problem with off the shelf reading glasses is that both lenses are made exactly the same and don't take into account each individual's needs. Most people don't have the same exact impairment in each eye so the need to upgrade to a fitted pair from an optometrist may be needed.

Computer eyewear is another form of glasses taking the market by storm. With over 88 million people using a computer regularly for work or school, this type of vision correction is a burgeoning market. Computer glasses help to cut down on monitor glare as well as help prevent strain on they eyes since you read at a different distance and size than normal printed material.

Find out more on reading glasses at Wikipedia, the AC Lens vision care center, or contact your optometrist.

About the Author

Frank Drummond is a freelance writer from Cleveland, OH with a specialization in the health, sports, and technology fields. He can be contacted at frankdrummond63 ( at ) yahoo.com. This article on designer reading glasses was written on behalf of Arlington Contact Lenses.

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