Have you ever wondered how those tiny, clear discs known as contact lenses can help correct your vision? Millions of people around the world rely on contact lenses every day to see clearly, but what is the science behind these incredible visual aids?
Keep reading to learn what contact lenses are, how they work, and who can benefit from them!
What Are Contact Lenses?
Contact lenses are thin, curved discs made of transparent plastic materials that are placed directly on the surface of the eye. They float on the tear film layer that covers the cornea, the clear front part of the eye.
Contact lenses are designed to correct refractive errors, which are vision problems caused by irregularities in the shape of the eye that prevent light from focusing properly on the retina. There are many different types of contact lenses, from daily wear to monthlies, single vision to bifocal, and custom lens options for unique needs or difficult fits.
Soft contact lenses are the most common type of contact lenses and are made of flexible plastics that allow oxygen to pass through to the cornea. They are comfortable to wear and come in a variety of replacement schedules, from daily disposables to lenses that can be worn for up to a month.
However, there are other types of contact lenses, such as RGP or rigid gas permeable lenses, that are better suited for certain people. Your eye doctor at Blaine Eye Clinic in Blaine, Minnesota, will recommend the best contact lens option for your eyes and lifestyle.
How Do Contact Lenses Correct Vision?
To understand how contact lenses correct vision, it’s helpful to know a bit about how the eye works. When light enters the eye, it is refracted or bent by the cornea and the lens inside the eye.
This focuses the light onto the retina, the light-sensitive tissue at the back of the eye that converts light into electrical signals that are sent to the brain, allowing you to see. In a perfectly shaped eye, the cornea and lens focus light directly onto the retina, resulting in clear vision.
However, if the eye is too long or too short, or if the cornea is irregularly shaped, the light may focus in front of or behind the retina, causing blurred vision. This is where contact lenses come in.
Contact lenses work by altering the way light is refracted as it enters the eye. They essentially become the first refractive surface that light encounters, taking over the role of the cornea in focusing light.
The precise curvature and thickness of the contact lens are designed to make up for the eye’s refractive error, making sure that light is focused directly onto the retina for clear vision. For people with myopia or nearsightedness, contact lenses are made to be thinner at the center than at the edges.
This corrects the eye’s tendency to focus light in front of the retina. For those with hyperopia or farsightedness, the lenses are thicker at the center, helping the eye to focus light directly on the retina rather than behind it.
What Are Toric Contact Lenses?
In addition to correcting nearsightedness and farsightedness, contact lenses can also address astigmatism, a refractive error caused by an irregularly shaped cornea or lens. Astigmatism results in distorted or blurred vision at all distances.
To correct astigmatism, a special type of contact lens called a toric lens is used. Toric lenses have different powers in different meridians of the lens, allowing them to correct the asymmetric curvature of the eye.
They also have a design feature that keeps them oriented correctly on the eye, ensuring that your vision stays stable. Toric contact lenses are available in both soft and RGP forms.
While soft toric lenses are more commonly prescribed due to being easier to use and more comfortable, RGP toric lenses can provide sharper vision for some people with higher amounts of astigmatism.
Can Anyone Get Contact Lenses?
While contact lenses are a fantastic vision correction option for many people, not everyone is a good candidate for wearing them. A comprehensive eye exam with your eye doctor is necessary to determine if contact lenses are right for you.
During the exam, your eye doctor will evaluate your overall eye health, take precise measurements of your cornea and eye shape, and discuss your lifestyle and visual needs. Certain eye conditions, such as severe dry eye or corneal irregularities, may make wearing contact lenses challenging or inadvisable.
Age can also play a role in contact lens candidacy. Children and teenagers can wear contact lenses, but they must be responsible enough to follow proper lens care and hygiene practices.
On the other end of the spectrum, adults over forty may begin to experience presbyopia, a natural age-related loss of close-up focusing ability. Multifocal or monovision contact lenses can help address presbyopia, allowing continued clear vision at all distances.
If you and your eye doctor determine that contact lenses are a good choice for you, you’ll then have a contact lens fitting to find the best lens material, size, and power for your individual needs. Your eye doctor will also provide training on how to safely insert, remove, and care for your lenses to ensure healthy, comfortable wear.
Contact lenses are a marvel of modern optometry, offering a convenient and effective way to correct a wide range of vision problems. By understanding how these tiny lenses work and who can benefit from wearing them, you can make an informed decision about whether contacts are the right choice for your visual needs.
Are you interested in exploring contact lenses? Schedule an appointment at Blaine Eye Clinic in Blaine, MN, today!
