What is "contact lens"

n. A thin lens, made of flexible or rigid plastic, that is placed directly on to the eye to correct vision, used as an alternative to spectacles, or, if coloured, to change one's eye color cosmetically.

n. a thin curved glass or plastic lens designed to fit over the cornea in order to correct vision or to deliver medication [syn: contact]

A contact lens, or simply contact or CL, is a thin lens placed directly on the surface of the eye. CLs are considered medical devices and can be worn to correct vision, or for cosmetic or therapeutic reasons. In 2004, it was estimated that 125 million people (2%) use CLs worldwide, including 28 to 38 million in the United States. In 2010, worldwide CL-market was estimated at $6.1 billion, while the U.S. soft lens market was estimated at $2.1 billion. Multiple scientists estimated that the global market would reach $11.7 billion by 2015. , the average age of CL wearers globally was 31 years old, and two thirds of wearers were female.

People choose to wear CLs for many reasons. Aesthetics and cosmetics are the main motivating factors for people who want to avoid wearing glasses or to change the appearance of their eyes. Others wear CLs for functional or optical reasons. When compared with spectacles, CLs typically provide better peripheral vision, and do not collect moisture (from rain, snow, condensation etc.) or perspiration; this makes them ideal for sports and other outdoor activities. CL wearers can also wear sunglasses, goggles, or other eyewear of their choice without having to fit them with prescription lenses or worry about compatibility with glasses. Additionally, there are conditions such as keratoconus and aniseikonia that are typically corrected better with CLs than with glasses.

Contact lenses market is likely to grow due to the increasing occurrence of eye related conditions such as astigmatism, hypermetropia and myopia. The other drivers of this market are increasing population, fashion statement and technological advancement. By the end of 2020, the market value is predicted to reach US$13.50 billion.