What are Contact Lenses Made Of?
Millions of people wear contact lenses to change up their look, correct their eyesight, and safeguard hurt eyes. Contacts' success comes down to their affordability, comfort, efficacy, and safety.
Contact lenses can be divided into three categories: soft, rigid gas permeable (RGP), and hybrid. This article will look at what each of these contact lenses is made of. So, let's dive right in!
What are Contact Lenses Composed Of?
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Soft Contact Lenses
Plastic, but not the kind of plastic used to make rubbish bags and water bottles, is used to make soft contact lenses. Hydrophilic plastics—a unique kind of water-absorbing plastic that retains its softness and moistness even after extensive water absorption—are used to make soft lenses.
You probably notice how this material functions when you use soft contacts. If your contacts become dry, they become so fragile that they can even break. The plastic remains malleable and soft as long as it's kept nice and moist on the eye or in a case.
This gentle suppleness is comfort on your eyes! Your lenses will start to feel unpleasant if your eyes are dry as they need water to stay in place and be flexible. The water content in soft contact lenses determines what class they belong to - they fall into the high-water or low-water categories.
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Long-Wear Soft Contact Lenses
Most extended-wear contact lenses comprise of silicone hydrogel, a substance that blends silicone and the water-absorbent plastic of soft lenses. The hydrogel plastic is given silicone to produce a lens that retains moisture and permits more oxygen to pass through the contact lens and into the eye—because of this, using contact lenses doesn't harm the eyes. This substance was added to extend the wear of contact lenses, with the additional advantage of increasing eye moisture and oxygenation.
Anyone who wears lenses for a prolonged period requires contacts that enable their eyes to breathe. The silicone layer provides this capability for optimum contact lens health.
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Rigid Gas Permeable Lenses
Another type of plastic used in lenses is rigid gas permeable (RGP) lenses. In contrast to soft contact lenses made of plastic, rigid gas-permeable lenses carry oxygen without moisture absorption.
As an alternative, RGP lenses include tiny pores that let oxygen pass through. Because of this, RGP lenses are categorised according to their oxygen permeability rather than their moisture content. Three materials now make up the majority of RGP lenses: acrylate, silicone, and fluorine.
RGP lenses are occasionally referred to as "hard" lenses; however, they differ from the "hard" lenses of the past, which were mostly made of acrylate. Because not enough oxygen can pass through this material, this type of contact lense is generally no longer recommended.
Over time, lens producers increased oxygen permeability by adding silicone. Later, they added Florine to assist in maintaining the moisture of the lenses while maintaining their form. Due to their ability to maintain their shape, they can be utilised to treat conditions affecting the eyes, such as keratoconus (when the cornea is deformed).
Some people who wear contact lenses like having a more visual experience because of their lenses. They also appreciate the improvement in eyesight that comes with wearing a stiffer lens that remains in place on the eye.
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Hybrid Contact Lenses
There are hybrid contact lenses that blend the components of an RGP lens and a soft contact lens, albeit they are relatively uncommon. For sharper central vision, these lenses feature an acrylate-silicone-fluorine compound in the center and soft contact lenses with moisture-absorbing hydrogel around the borders.
These hybrid lenses are frequently used for uneven astigmatism treatment or even for multi-focal lenses (bifocal or advanced contact lenses).
How Long Should Contact Lenses Be Worn For?
Everyone who used contact lenses removed and sanitized them each night up until 1979. The development of "extended wear" then allowed users to sleep with their contacts. Now, two lens kinds are separated based on how long they are worn:
- Daily wear — must be removed nightly
- Extended Wear – wear continuously for an extended period of time—typically for seven days straight, without removing.
The maximum wearing period for some types of extended-wear contacts of 30 nights in a row, referred to as "continuous wear."
When Should You Replace Your Contacts?
Even with adequate maintenance, contact lenses—especially soft lenses—should be changed often to avoid contamination and lens coatings that increase the likelihood of eye infections.
Depending on how often they should be replaced, soft lenses can be divided into the following broad categories:
- Daily-use Contact Lenses: Throw them away after a single day of use.
- Disposable Lenses: Toss away every alternate week or earlier
- Frequently Replacement Lenses: Discard every month or every three months
- Traditional Lenses: Throw away after six months or more.
Gas-permeable contact lenses do not have to be thrown away as often as soft lenses since they are more resilient to lens buildup. GP lenses frequently last a year or more before needing to be replaced.
Monthly lenses was the most popular schedule for prescribing contact lens replacements in the United States in 2017 (40%), trailed by daily (35%) fortnightly (24%), and yearly (1 percent).
So, Which Contact Lens is the Perfect Fit for You?
Your lenses must first deal with the issue that initially led you to need lenses. Myopia, hyperopia, astigmatism, or a combination of these vision issues must be corrected by your contact lenses to offer clear vision.
The lens must also suit your eye correctly. To do this, lenses are available in tens of thousands of different diameter and curvature configurations. Of course, not all lens brands provide their products in all "sizes." Your optician is qualified to assess your eye's and your vision's physiology to determine which lens best meets the two aforementioned requirements.
Another medical necessity may influence the choice of a lens. For instance, if your eyes are prone to dryness, your optician might recommend a specific lens. You'll receive a contact lens prescription when you and your optician choose the best lens. At MiEyes, we sell various brands of contact lenses to suit these various needs.