subject: Contact Lenses [print this page] The idea of contact lense was initially suggested in 1508 by Leonardo da Vinci. Contact lenses have been improving for years by its forerunners. Up to this point, , there are numbers of improvement of various types of them such as prescription, therapeutic and fashion contact lenses.
Contact lenses characteristics are classified into soft and rigid gas permeable (RGP) contact lenses. They are produced of material ( permeable polymers) that allows enough oxygen to to reach the eye cornea. When it comes to ease of use , soft contact lenses are more comfy to use than other.. RGP contact lenses need longer adaptation for user's convenience. A few of soft lenses have UV protection shell to safeguard the natural eye. In contrary to Rigid Gas Permeable lenses, soft lenses are more fragile and are more prone to eye contamination attributed its thinner wrapping. RGP has also its edge over the latter it terms of its application for it is easier to put and remove.
Daily disposable and extended wear are the two categories of wear schedule. Daily disposables are also called one-day disposable. These are perfect for sensitive and allergic eyes. Since daily disposable lenses don't need clean-up, some people regarded it as more convenient than the other. These kinds of soft contact lenses are only put on in daytime and thrown away before sleeping. On the contrary, extended wear lenses are useful for certain period of time without removal. There are two varieties of extended wear lenses, there are lenses that are utilized over a week and others are the ones that can be used in a thirty days. The lenses that can be used in one month are called super permeable for they have Silicone Hydrogel which provides more oxygen in comparison to other lenses..
In terms of usability, contact lenses can be used for eye problem correction and fashion. There are various types of cosmetic lenses to choose from such as light-filtering tint, enhancement tint and color tint. Color tints alter the shade of the eyes into different colors but mostly violet, amethyst and green. There are also lenses designed for sports known as light-filtering tints. Light filtering tints mute specific colors. To enhance the natural color of the eye, enhancement tints are perfectly designed.
When it comes to correction modality, there are bifocal, toric and Orthokeratology lenses that treat certain eyesight problems. Bifocal contact lenses are intended for an eye that is experiencing inability to focus on near objects referred to as presbyopia .Lenses for presbyopia could be manufactured either in soft or rigid gas permeable materials. It may be disposable or monthly wear. Toric contact lenses are made for astigmatism, an eye blurry image. They come with soft and rigid gas permeable material. Apart from astigmatism, it is also intended to fix nearsightedness or farsightedness problem. Orthokeratology lenses are also called Corneal Reshaping contact lenses that temporarily cure nearsightedness or mild myopia eye disorder. These special lenses are worn out throughout sleep and taken out after awakening. The material used by this is rigid gas-permeable.
There are lenses which are also therapeutic called bandage lenses. They are the kind of lenses treat eyes diseases in cornea and anterior such as corneal edema, keratitis, corneal ectasis, corneal edema, descemetocele and a lot more.
Contact lenses have been developed and even more developing soon. Anybody could easily pay for discounted contact lenses in various forms. Nevertheless, qualified Ophthalmologist's advice ought to be drew on before getting contact lenses. Moreover,careful purchasing should be regarded, it should be FDA approved. Contact lenses may provide people a great help but proper use of it should not be overlooked.
