Types of Lenses
Soft Contact Lenses
These are the most common and popularly worn contact lenses. They are made of soft, flexible plastics that allow oxygen to pass through to the cornea. These are relatively easy to adjust to and are more comfortable than most other types of hard to semi rigid lenses. The newer soft lens materials include silicone-hydrogel lenses which allows more oxygen to enter your eye while you wear your lenses.
Rigid Gas Permeable (RGP) Contact Lenses
Rigid gas permeable contact lenses (RGPs) are another common variety that are known to give a clearer and crisper view. They are more durable and resistant to deposit buildup and are easier t handle and less likely to tear. They are typically cheaper than the others types of lenses as they last longer. The only disadvantage is that they may take weeks to acclimatize to as compared to a few days or even instantly in the case of soft lenses.
Extended Wear Contact Lenses
As the name suggest extended wear contact lenses are used for overnight or continuous wear ranging from one to six nights or up to 30 days. These are typically soft contact lenses and are made of flexible plastics to allow oxygen to pass through to the cornea. There are also a few rigid gas permeable lenses that are designed and approved for overnight wear. Length of continuous wear depends on lens type and your eye care professional’s evaluation of your tolerance for overnight wear. It is essential to remember that the must have a rest without lenses for at least one night following each scheduled removal.
Disposable or Replaceable Contact Lenses
Most of the people wearing soft contact lens wearers are prescribed some type of frequent replacement schedule. “Disposable,” as defined by the FDA, means used once and discarded. With a true daily wear disposable schedule, a brand new pair of lenses is used each day. However, most disposable contact lenses are discarded after a use of 7 to 30 days. The lens wearer is prescribed a replacement schedule after which the lens need to be changed.
Read more about colored contact lenses and their uses on colored soft contact lenses.