Prescription eyeglasses are necessary to help correct your vision if you can’t see properly. There are many different types of lenses, and the type you need depends on your particular vision problem.
If you have a single problem, such as farsightedness, nearsightedness or astigmatism, the lenses you need are different than if you have more than one vision problem.
Simply stated, the lens is the tool that your eye uses to focus light onto your retina in the correct way.
You can also choose various types of coatings to enhance your lenses, such as an anti-reflective or anti-scratch coating.
Single vision lens eyeglasses
Single vision prescription lenses correct one vision problem, such as nearsightedness or farsightedness.
They only have one optical correction, and they have the same focal power over the whole surface of the lens. Single vision prescriptions only state one type of corrective power. This can be a minus (-) or a plus (+).
You are shortsighted if objects appear fuzzy at a distance, but you can still see objects up close.
Convex, single vision lenses can correct this problem as they help to focus a visual image directly on the retina instead of in front of it.
If you are farsighted, you may have difficulty reading because it is hard to see up close. You can wear concave, single vision lenses to correct this problem. The lenses focus the visual image directly on the retina instead of behind it.
Most people who have to wear eyeglasses before the age of 40 wear single vision lenses. If you need single vision prescription glasses, fast delivery is possible. Place an order online and select rush service if you want UPS next day air delivery.
Eyeglasses for astigmatism
Astigmatism is a common condition that describes when your cornea is unevenly curved. One side is more curved than the other, and this causes a refractive problem that gives you blurry vision.
Apart from blurry vision, you may have difficulty seeing at night, headaches, and eye strain.
You can have astigmatism in just one eye or in both. You may have astigmatism and nearsightedness or farsightedness, in which case both need to be corrected. The term CYL on your prescription indicates what cylindrical correction to the lens is needed to correct your unevenly shaped cornea. The higher the CYL, the more astigmatic your eye is.
On the prescription, you will also see a box marked AXIS. This is measured at an angle to compensate for the asymmetry.
This angle could be anywhere within 180 degrees. Wearing the right prescription lenses for astigmatism helps the light to pass through the lens and focus on the retina in the correct place.
Multifocal Eyeglass Lenses
If you have more than one vision problem, you can’t use single vision lenses. Multifocal lenses contain two or more vision-correcting prescriptions. They come in three different options – bifocal, trifocal and progressive.
Bifocal lenses have two focal points. The upper part of the lens is normally for distance vision, and the lower part is for near-vision tasks like reading.
You can see both near and far without having to change your glasses. The line between the two prescriptions is visible.
Trifocal lenses have three focal points – near, intermediate, and far. You will see up close with the bottom of the lens, move to the middle for intermediate distance, and the top is for distance vision.
Progressive lenses also contain three fields of vision – near, intermediate and distant – but there is no visible line between prescriptions.
You have a seamless transition when looking from objects up close to when you look at those from far away.
Progressive lenses are equivalent to three single vision lenses in one, which is why they are more complex to make and more expensive.
Eyeglasses with polarized lenses
Eyeglasses with polarized lenses are ideal for you if you take part in sports such as sailing, windsurfing, fishing or skiing.
They have a special coating that filters the light from different angles. This removes glare, so you have crisp, clear vision.
Your eyes are protected from glare reflected off the surface of the water or the snow, which can be blinding.
Other Lens Enhancements
There are various lens enhancements you can choose that offer better performance. If your eyes feel strained after looking at digital screens for long periods, blue light protection may be necessary.
This protective coating helps to eliminate eye strain and fatigue. It can also help you to sleep better as blue light interferes with your sleep patterns.
Anti-reflective coating helps to provide a sharper image by reducing reflections. It can also shield your lenses from dust and scratches. Sometimes, a light or dark hint of color on the lens can help you see better.