There is a vast range of contact lenses available on the market today. to have the most suitable for our eye need, we have some understanding of these contact lenses and know their differences. The following will give some introduction about the different categories of contact lenses in the hope of giving people more help in choosing the best lens for themselves.
The main common types of contact lenses are hard and soft lenses. Hard and soft Lenses are made of various types of polymers, which usually contain some different types of hydro gel. At the beginning, hard contact lens was made of a polymer called PMMA, but he cannot allow oxygen to get through it to the eyeball, so that people feel uncomfortable or irritated to use them. Is then introduced rigid gas permeable contact lens, short for PSI.Nowadays, PSI and soft contact lenses are made of hydrophilic material, which is a species of water absorption material and can allow more oxygen get through it and get our cornea. therefore, the lenses are comfortable to use.
How the hard lens is replaced by rigid gas permeable lens, then the main types of contact lenses are soft lens and rigid gas permeable lens. Both have their own advantages. For soft contact lens, it is easier and more comfortable to use as is mobile and can allow more oxygen reaching our cornea.And RGP lenses allows people to have a clearer picture of how the lens is tougher. Furthermore, RGP lenses are more durable and can be used to the life expectancy. Both rigid gas permeable lenses and soft disposable lenses may enter into and soft lens is more popular for disposable lens, which can be used from seven to 30 days on the basis of their specific use and characteristics.
In addition to disposable contact lenses, for people who need to use the lens to almost all the time, they can choose prolonged contact lens. Most prolonged contact lenses is soft contact lenses, while some are rigid gas permeable lens.The prolonged contact lens can be used for the specific requirement of time without removing them and until his valid date, we only may discard them.
Another type of contact lens is the specialized contact lens called ortho-k.With the help of Ortho-K, we can change the curve in our cornea temporarily, but it is not a permanent solution. that'll be good to prevent eyes still and keeping the curvature of the cornea.
For users of contact lenses, there are some tips on cleaning and maintenance, we follow. in case we missed a lens, or our eyes get infected, it is best to bring a pair of goggles with us and before handling the lenses, is a must for washing your hands.
