Rigid contact lenses and soft contact lenses difference

Rigid contact lenses and soft contact lenses difference
Brief content:Our commonly used contact lenses, can be divided into three kinds on the whole at present. Each have their own advantages, will have shortcoming of all kinds inevitably in these three kinds of contact lenses. Having only understood the characteristics of these three kinds of contact lenses, could be chosen most suitable that style.
A rigid contact lenses (HCL) : The material is the plastics (PMMA) of a kind of high purity ,The sense of foreign matter is relatively strong while wearing the mirror at first, generally takes 2 --Can basically suit until 3 weeks. Correct the result to long sight, near-sighted and somewhat astigmatism well, use and attend to simply, conveniently, the expenses are low, durable and durable, can use 3 --4 years or a longer time. The size is smaller than the cornea, the diameter is about 8.0 --9.5mm, for make patient wear, spend comfortable, guarantee harmony that tear exchange, need some time in designing.
2 soft contact lenses (SCL) : The material is a to kiss the swimming skill and formate the macromolecular compound, is divided into again low and moisturely according to the amount of water content (30%) , middle moisture (30%~60%) , it is high and moisture (60%) . Water content makes the lens soft, whippy high, completely oxygen is good, there is no obvious foreign matter sense while using at first. However, because it is a soft material of a kind of aquosity, it is easy pollution or stale, so must carry on strict disinfection. In addition compared with rigid contact lenses, it is relatively bad in correction of the astigmatism, need to use the special astigmatism to use the lens, service life is 1 --1.5. Wear and use the comfortable characteristic that is greatest. The lens is larger (12.5 --14.5 millimetres) ,Cover the cornea in an all-round way, dust foreign matter is difficult to enter eyes, it is not apt to shift, loss either, wear when being very suitable for participating in the sport activity.
The soft contact lenses can absorb the moisture, permeate the oxygen, soft and crooked, it is few to stimulate the cornea, accord with requirement of breathing supersession of the cornea, can be used in the rescuing of the general myopia, long sight and astigmatism, it is the main products of the contact lenses at present.
Advantage: There is good plasticity, it is very comfortable to wear, adaptation time is short. Because needn't suit repeatedly, so for the intermission to wear! The diameter is relatively large, the edge of the lens lies under upper eyelid, has avoided the foreign matter sense that the friction of eyelid and lens edge causes, and the lens will not be lost from the eyes out. Utilize flexibility, hydroscopicity, having a greater diameter characteristic its, can use as eyes table illness getting therapeutic to use. The edge of the lens is enclosed outside the scleral edge of angle closely, it is difficult to be perceived, so appearance is esthetic. Stainable or tint cosmetology and reshape used in the eyes.
Shortcoming: The material is low in intensity, easy damage. Lens plasticity is strong, it is relatively bad to correct the cornea astigmatism result. Surface polarity is strong, apt to absorb the precipitate in the tear, pathogenic microorganism and attend to the composition of the liquid, cause eyes complication, wash and disinfecting procedure require strict, must consider lens and compatibility to attend to product. Most performance ideal enough even oxygen completely of lens, can't wear overnight.
3 ventilative rigid contact lenses (RGP CL) : Strong point (optics is good, uses simply and conveniently etc.) with all general rigid contact lenses ,Have ventilative performance at the same time, there are less impacts on cornea, material also more ordinary hard mirror is soft, but service life is relatively short, it is 2 --In 3, some materials were easy and was adhered to by things such as the albumen in the tear,etc., except that it is regular to carry on and wash every day, still need to deal with other special lotion. It is apter to suit to wear the mirror at first, only takes 1 --2 weeks. Generally can use 12 every day --16 hours, can also wears and uses continuously for a long time according to the need. The ones that present after plucking the mirror look at things the fuzzy, fog is looked at less, it is apt to use with ordinary glasses, also a great strong point of this kind of lens.
RGP wears on the surface of eyes as SCL, changes crooking all state of eyes on the whole, so as to correct and crook all purpose not positive.
Advantage: RGP have good shaping nature, apt to deform, it is high in quality for optics to correct, especially until near-sighted high patient of astigmatism it corrects the result to be better highly. As to various irregular astigmatism of cornea that reason lead to the fact ' If taper cornea, cornea crook the light and perform the operation, wait after the traumatic operation) ,RGP can not only improve and correct the visual method effectively, can also control the development of disease, play a role in treating.
RGP does benefit to washing, protein, fat precipitate little, it is simple and convenient to attend to the course, the inflammatory incidence is low, high oxygen completely its, lens diameter little, interfere with normal physiological supersession activity of eyes, have better compatibility with eyes, safer than SCL, is suitable for wearing crooking all not chief patient of the contact lenses for a long time.
Shortcoming: Because RGP is made of special material not containing water, the texture is relatively hard, there is a slight foreign matter sense while wearing for the first time, adapt to one than SCL long; When being engaged in the violent sports activity, its stability is not so good as SCL, to wear is not so comfortable as SCL; And must make the lens into the camber of negative camber of many kinds of specifications, adapt to different wearing the eyes, having increased the difficulty of testing and buying technology, the price is comparatively expensive.
The editor recommends:Method of protecting eyes and skin of the computer clan
|