Types of Contact Lenses
Contact lenses can be classified in many different manners. The classifications are based on its functions, constructional material, wear time, frequency of replacement and design or implantation. There are corrective Contact Lenses which are especially designed to improve your vision. Such contact lenses rectify the vision problems in your eyes- myopia (short sightedness), hypermetropia (long sightedness), astigmatism and presbyopia. Sometimes, "X-Chrom"contact lens or ChromaGen lenses might be used depending on the wearer eye condition.
Cosmetic contact lenses are often worn by men and women to change the color of their eye. These lenses may also correct the vision, but these are mostly used for giving color to your eyes. These types of lenses might cause some irritation to your eyes, therefore, these lenses are advised not be worn too much.
Theatrical contact lenses are mostly used by those acting in horror films or zombie movies. These lenses make your eye appear arousing. Scleral lenses are used in many theatrical lenses. It covers the white part of the eye and is not worn for more than 3 hours. Other such lenses are also available in the market which gives your eyes a different appearance.
There are therapeutic Contact Lenses which are used for the treatment and management of non-refractive disorders of your eye. These lenses are used to treat eye conditions including dry eyes, corneal ulcers and erosion, bullous keratopathy, corneal edema, descemetocele, keratitis, corneal ectasis, anterior corneal dystrophy, Mooren's ulcer and neurotrophic keratoconjunctivitis.
William Feinbloom has introduced lenses made from polymethyl methacrylate. They are called PMMA lenses or "hard" lenses. However, these lenses have many side effects and therefore, they are not much popular. Before the launch of sot lenses, people used to wear rigid lenses, which offer a variety of exclusive properties. You can also get a few hybrid rigid/soft lenses in the market.
Some contact lenses are classified according to their wear time. These are daily wear contact lens, which can be removed before sleeping. There are extended wear (EW) contact lenses, which can be worn overnight. Besides, there are Disposable Lenses which can be thrown after every use or a specific period of time. These shorter replacement cycle lenses are thinner and lighter.
Similarly, there are lenses for longer replacement cycle. Contact lenses, which can also be classified according to their design include, spherical contact lens, toric lens, rigid gas permeable bifocal contact lens and multi-focal soft contact lenses.
