Approximately $8 billion was spent on eye in the United States care in 2009, according to reports from market research company IBIS World, with more than 20,000 establishments and companies offering prescription reading eyeglasses and contacts in America. The "Contact Lens Spectrum" estimated the total number of contact lens wearers worldwide in 2005 to be 125 million people, with nearly 38 million of them living in the United States. The exact number of reading glass wearers is unknown, due to the difficulty of tracking over-the-counter, non-prescription sales.
Function
Both reading eyeglasses and contact lenses correct vision problems. The term "reading glasses" is used to describe glasses prescribed for up-close vision. Myopia, a vision issue that interferes with the ability to see items in close proximity, requires wearing reading glasses. These may be either over-the-counter models, also known as "readers," made in standard correction grades, or specialized glasses made with optical glass prescribed for individual wearers. Bifocals incorporate two lenses, both readers and regular vision correction. Contact lenses, unless they are manufactured as bifocals, must be used with reading glasses to see items at arm's length.
Types
Contact and eyeglass lenses are custom-made to improve or correct vision. The earliest known use of glasses in history dates to European monks in approximately 1000 A.D. This practice was later reported by English author and philosopher Roger Bacon in 1268, according to California M.D. Richard D. Drewry, Jr. A major innovation in spectacles was the development of lenses correcting nearsightedness in the 16th century. American statesman, historian and inventor Benjamin Franklin is given credit in the 1780s for inventing the bifocal, a combination lens suitable for both reading and distance correction.
While the concept for contact lenses was introduced in 1845, lenses were not available in the United States until the 1940s. By the mid-1960s nearly six million people used contacts, according to Dr. Drewry. Modern contact lenses typically use soft, transparent plastic, although hard plastic contacts known as rigid lenses are still prescribed and sold.
Effects
Wearing both reading glasses and contact lenses tires the head and eyes. The ears may tire from the pressure of the glasses, and contact lenses also irritate the eyes of some wearers."The Contact Lens Spectrum" reports that nearly 10 percent of contact lens wearers discontinue their use each year. Frequent complaints, according to the contact lens industry publication, included "discomfort, hassle and application/removal difficulties."
Considerations
The Ohio State University Medical Center states that nearly 24 million people in the United States wear contact lenses. More than 80 percent of this number wear daily-use soft contact lenses. Not everyone who requires vision correction, however, has the option of wearing contact lenses. People with extreme curvature of the eye or extremely dry eyes are not suitable candidates for contacts, according to the OSU Medical Center.
Benefits
There are advantages and disadvantages for both types of vision correction. Contact lenses, both hard and soft, have the advantage of leaving the face free from a glasses frame. Reading eyeglasses have the advantage of easy removal when not in use, while hard contacts require a regimen for cleaning and storage. Disposable contacts may be worn for longer periods of time and do not require the lengthy cleaning procedure, but the cost is higher than for a pair of glasses when calculated over the average life for a pair of reading glasses.
References
- Ohio State University Medical Center: Eye Glasses and Contact Lenses
- IBIS World: Eye Glasses & Contact Lens Stores Industry Research
- Canadian Centre for Occupational Health and Safety: Contact Lenses at Work
- Teagle Optometry: What ManDevised That He Might See; Richard D. Drewry, Jr.
- "Contact Lens Spectrum:" Joseph T. Barr; Jan., 2005
