Contact lenses are thin, curved lenses placed on a film of tears that cover the eye surface. Naturally, it is clear but sometimes given some tinge of color for easier handling. Nowadays, contact lenses can be soft or hard. Most people prefer soft lenses, although they were previously glass blown. When you need vision correction, contact lenses are best since they offer a crisper and clear vision as they are on the eye. Also, they support active lifestyles and improves your look when you use tinted or colored lenses. If you need to know more about soft or hydrophilic contact lens you can check out the comprehensive article about them. It was written as a compelling tribute to Otto Wichterle, credited with creating the first hydrogel contact lens.
Below are some types of contact lenses:
Soft Contact Lenses
Soft or silicone hydrogel lenses are made of very flexible, soft plastics that absorb water up to 90 percent of the weight of the lense. To many people, they are comfortable than the hard lenses. However, the hard lenses provide a sharper vision.
In addition, soft lenses require careful handling since they are fragile and need more cleaning. Many soft contact lenses include daily wear lenses that you remove to clean every night and reinsert in the morning. Also, there are extended wear lenses that you can wear day and night and disposable lenses that you wear for several weeks then discard.
Rigid Gas Permeable Contact Lenses (RGP)
The RGPs are more durable as they resist the deposit of buildup to give a crisper, clearer view. They are less expensive in the long run since they last longer compared to soft contact lenses. Also, they are easier to handle, taking a long time to tear. However, they are not as comfortable as soft contacts. Therefore, it might take some weeks to adapt to wearing RGPs, compared to soft lenses that take several days.
Extended Wear Contact Lenses
Extended wear lenses are for continuous or overnight wear that ranges from six nights to one month. These lenses are soft contact lenses made from flexible plastics to allow oxygen to pass to the cornea. There are few rigid permeable lenses designed and approved for overnight use. The length of continuous wear will depend on the type of lens and the eye care professional evaluation on your tolerance to overnight wear. Your eyes must have some rest without the lenses for at least one night after each removal.
Hybrid Contact Lenses
They are for wearing comfort that rival silicon or soft hydrogel lenses, with crystal clear optics of a gas permeable lense. A hybrid lens has a rigid central zone surrounded by silicone or hydrogel material. Despite the features, only a few people wear hybrid contact lenses. The lenses are expensive to replace and difficult to fit compared to silicone hydrogel and soft lenses.