A contact lens Oakville, or simply contact or contact lens Oakville, is a thin lens placed directly on the surface of the eye. Contact lens Oakville 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 Contact lens Oakville worldwide, including 28 to 38 million in the United States. In 2010, worldwide Contact lens Oakville -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. As of 2010, the average age of Contact lens Oakville wearers globally was 31 years old, and two thirds of wearers were female.
People choose to wear Contact lens Oakville 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 Contact lens Oakville for functional or optical reasons. When compared with spectacles, Contact lens Oakville 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. Contact lens Oakville 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 Contact lens Oakville than with glasses.
Corrective Contact lens Oakville are designed to improve vision, most commonly by correcting refractive error. This is done by directly focusing light so it enters the eye with the proper power for clear vision. Recently, there has been renewed interest in orthokeratology, the correction of myopia by deliberate overnight flattening of the corneal epithelium, leaving the eye without a refractive error during the day.
A spherical Contact lens Oakville bends light evenly in every direction (horizontally, vertically, etc.). They are typically used to correct myopia and hypermetropia. A toric Contact lens Oakville has a different focusing power horizontally than vertically, and as a result can correct for astigmatism. Some spherical rigid lenses can also correct for astigmatism. (See below.) Because a toric lens must have the proper orientation to correct for a person’s astigmatism, such a Contact lens Oakville must have additional design characteristics to prevent it from rotating away from the ideal alignment. This can be done by weighting the bottom of the lens or by using other physical characteristics to rotate the lens back into position. Some toric Contact lens Oakville have marks or etchings that can assist the eye doctor or the user in fitting the lens. First disposable toric Contact lens Oakville were introduced in 2000 by Vistakon.