Types of Contact Lenses
There are various types of contact lenses available in the market. Your eye doctor will be able to help you choose the correct lenses needed to suit your requirements.To know more about caring for your contact lenses read How to wear and care for your lenses
The first lenses developed in the 1960s were the rigid or "hard" contacts. They are made of a type of plastic called PMMA (polymethyl methacrylate). They are long lasting, but do not allow oxygen to reach the cornea. When the eye blinks, the lens moves, which allows the oxygen dissolved in the tears to reach the cornea. Rigid lenses are not very comfortable and are not used today. They are preferred only for their durability and lower cost.
These lenses are also known as "RGPs." They are rigid or hard lenses made of plastics combined with other materials, such as silicone hydrogel contact lenses and fluoropolymers. Since they are gas permeable they allow oxygen to pass to the cornea.
Soft contact lenses
These lenses are made of plastic materials that carry water. The water makes them soft and flexible, and allows the oxygen to reach the cornea. Most people prefer soft contact lenses. Read more on advantages of soft contact lenses.
Daily disposable lenses
They are more expensive but carry a lower infection risk.
Extended wear contact lenses
made of material designed to last 2-4 weeks.
Toric contact lenses
These correct moderate astigmatism. They are available in both rigid and soft materials.
Generally, contacts should be removed at bed time due to risk of infection and risk of contact lens intolerance. They should always be cleaned and disinfected after removing and before wearing.
It is important to know the basic types of contact lenses available in the market today and different contact lens family available in the market.