Bifocals
If you find yourself constantly holding objects at arm's length to see them properly, you might be a candidate for bifocals. Bifocal lenses have two lens sections (hence the "bi" in their name). The first is for distance vision correction (your normal prescription) while the second is for reading or looking at close-up objects, such as a computer screen, up close. Usually, vendors dedicate most of the area of a bifocal lens to distance vision with a smaller section on the bottom half with additional lens power. However, this depends on the type of spectacles you buy. On traditional lenses, the high-power segment can take up the entire bottom half!
Bifocals tend to be popular among people with aging eyes. Having two lens powers makes it easy to shift between looking at objects at a distance and studying them up close. As such, you can eliminate the need for multiple prescriptions, potentially saving you money.
What Is A Bifocal Lens?
A bifocal lens is a lens that has two sections: a general-purpose area for standard long-distance vision and a smaller section, usually semi-circular, for reading and other close-up activities. Unlike progressives, bifocal glasses do not transition continuously between lens powers and have visible lines on the lens power boundary.
Bifocals have been around for nearly two centuries now and, in that time, manufacturing methods have improved significantly. Today's bifocal reading glasses are almost as attractive as those with progressive lenses.
There are several types of bifocal glasses available. These vary in appearance but not function.
Half-moon lenses have a D-shaped segment in the bottom half of the lens offering more power. Therefore, when users look down, they get extra magnification.
Round-segment lenses are similar however, this time, the higher-power area is circular, not semicircular.
Ribbon segment lenses are regular lenses in the top half and then have a narrow rectangular area at the bottom. These have a classic design that emerged in the second half of the 20th century.
Lastly, there are executive versions, sometimes called Benjamin Franklin bifocals after the founding father generally credited with inventing the concept. These feature enhanced power in the entire lower portion of the lens.
Essentially, all these bifocals work in the same way. However, you may prefer one style over another, particularly if you do a lot of reading.
How Are Bifocals Lenses Different From Progressive Lenses, Trifocal Lenses, And Multifocal Lenses?
Bifocals have two lenses: one for general vision, and one for near-vision correction. Progressive lenses, however, do not have any discrete sections at all. Instead, lens power varies continuously across their surface.
Trifocal and multifocal lenses are different again. Unlike progressive lenses, these do not vary lens powers continuously. However, unlike bifocals, they have three or more sections, the third being for intermediate vision correction.
Which you choose depends very much on your preferences. Many people choose bifocals because they are used to them. However, if you have focusing problems with objects a few feet away, you may want lenses with an intermediate segment for this purpose.
Traditional bifocal lenses look different from progressive lenses. That's because they have a visible line across their surface, separating the lens. Some people prefer this arrangement because it makes it easier to know where to direct their gaze for different activities. However, others dislike it because it distracts them from other objects in their field of vision.
At Eyeglasses.com, we offer a range of polycarbonate, ultra-thin, and glass bifocal lenses with almost imperceptible boundaries between the two viewing areas. Because of this, these look similar, if not identical, to progressive lenses. For all of these lenses, it is important to focus through the correct part of the lens for the object you want to see, because focusing problems will occur if you are trying to focus through the wrong part of the lens.
Who Is A Good Candidate For Bifocal Lenses?
There are several types of people who are good candidates for a pair of bifocals.
The first are people with presbyopia. Presbyopia is an age-related condition where the eye begins to change and lose its function. After the age of 40, the lens stiffens and hardens, losing its ability to shift focus between distant objects and those nearby. Over time, patients notice that reading material looks blurry, causing them to hold it at a distance or squint.
Second, those who already have a distance vision prescription can also benefit from bifocals significantly. Your eye doctor may recommend that you switch from your regular spectacles to bifocal glasses if you are having trouble seeing books or your phone clearly.
With that said, bifocals are not suitable for everyone. Those with significant intermediate vision requirements, for instance, may need trifocal lenses, particularly those who work at a computer screen or drive a vehicle and struggle to see objects between two and ten feet away.
You may also be a good candidate for wearing bifocals if:
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You who want the convenience of being able to see near and far objects through one lens
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You suffer from eye strain because you work at a computer screen
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You prefer using bifocal reading glasses because that is what you used in the past
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You notice that you are struggling with clear vision when reading up close
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You want eyeglasses that are for computer use
At EyeGlasses.com, we sell a range of trifocal and progressive lenses. In some cases, these may be better options. Our team can advise you on the best type of glasses to choose depending on your preferences, lifestyle, and vision needs.
What Are The Advantages Of Bifocal Reading Glasses?
Bifocal reading glasses offer a host of benefits compared to a standard prescription. These include:
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A distinct line separating the powers. Bifocal glasses make it easy to see which part of the glasses you should be looking through for greater clarity. On progressive lenses, this is not so obvious and you may have to spend several weeks, or even months, adjusting to them.
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A wide lens area for close-up work. Bifocal glasses provide more real estate than other options for near-vision tasks. The magnification zone takes up more of your visual field, reducing the need to keep your neck and body in the same position all the time.
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More affordable than progressive lenses. A single bifocal lens is also significantly cheaper to manufacture than a complex progressive one. Hence, the overall price of these glasses is significantly lower. Doctors often make the case that progressive lenses are the best value for money because they eliminate the need for separate prescriptions. But if your middle-distance vision is okay, then bifocal glasses are also a money-saver.
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Anti-reflective. Glasses can sometimes generate annoying glare that makes it difficult to see in direct sunlight or when standing underneath particularly bright LEDs. However, some bi- and trifocals come with anti-glare coatings that let you see clearly, no matter how bright it gets outside.
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Easy to adjust. Lastly, you may want to consider bifocal glasses because they are easier to adjust to if you are moving from single-vision spectacles. It can take people up to a month to adjust to progressive lenses because of the way the power varies across their surface. However, with bifocal glasses, you can use them straight away because they have distinct zones that mimic both regular and reading glasses. Furthermore, the risk of peripheral visual distortion is lower.
Are There Any Downsides To Bifocal Glasses?
Here are some potential downsides of bifocals you may want to consider:
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You may still need to adjust. While adjusting to bifocal glasses is easier than progressives, it can still take time to get used to them. You have to train both your head and eye muscles to adjust your vision to the right angle, depending on your situation. Eventually, your body will adapt, but it could be a steep learning curve for some people at the start.
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Visual distortions. You may also notice various visual distortions when using bifocal reading glasses, particularly in situations where you need to look down at your feet. For instance, you may struggle when climbing the stairs because of the additional magnification when looking downwards.
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Lines. Lastly, the lines on the lens may distract you. Most eyeglasses don't have any lines on them at all (unless they are heavily scratched). But with bifocals, it's a product feature. The good news is that your brain will eventually adjust.
Here at Eyeglasses.com, we supply a range of bifocal glasses with seamless transitions between them. These have an improved aesthetic compared to traditional designs.
Please note that some people may benefit from trifocal or progressive lenses more than bifocal glasses. We can consult with you about which option would be best and why so always talk to us first.
How To Use Bifocal Glasses
If you've never used spectacles with two lens regions before, it can take a bit of getting used to. However, with some practice, you can feel right at home with them in just a few days. Here's how to adjust quickly:
Make Sure You Have To Right Prescription For Distance Vision And Near Vision
Before getting bifocals, make sure that you are on the right prescription for both distance vision and near vision. Optometrists will have to build both types into the lens in advance to make something just for you. Don't rely on an old prescription as your site may have changed significantly since then.
Rotate Your Head In The Direction You Want To Look
Many people struggle with bifocals because they prefer to move their eyes to look at objects in their environment rather than their heads. If you can, try to avoid this tendency. That's because if you rely on eye movements, you will occasionally look down through the high-powered section at distant objects, distorting your vision (such as when walking downstairs).
Wear Them All The Time
Lastly, make sure that you wear your bifocal glasses as much as possible. The more time you spend with them, the more natural they will feel. Most people can get the hang of them within a couple of weeks if they practice regularly. You may find that you can adapt faster if you use the computer more often or do additional reading. Eventually, your brain will filter out any boundary lines between lens powers and they will feel perfectly natural.
The History Of Bifocal Lenses
Bifocal glasses have a rich and interesting history. Their story begins with founding father Benjamin Franklin, widely credited as the inventor of the original concept in the 1780s. Franklin wanted glasses that would let him study literature as he got older without having to change his spectacles every five minutes. His original design, though, was pretty basic. He simply stuck two different lenses together: one for the top half and one for the bottom.
Later, in the 19th century, French eye doctor Louis de Wecker developed a technique for fusing both upper and lower sections. In doing this, he was able to improve quality and reduce the likelihood of breakage.
Modern bi-focal glasses are significantly more sophisticated than these early versions. Manufacturing technology has moved on significantly. Today, manufacturers build several lens sections for multifocal lenses.
With that said, there is still a great deal of tradition in the industry. Modern designs often use the same formats as glasses from decades ago, mainly because of consumer preferences. People like their glasses, and they want to stick with them.
Get Bifocal Spectacles From EyeGlasses.com Today
If you're tired of frequently switching between glasses for regular use, reading, and the computer, you might want to consider bifocal spectacles. Once you get used to them, they make your life significantly more convenient, eliminating the need to carry multiple glasses around with you all the time.
At EyeGlasses.com, we stock the latest bifocal lenses offering the most advanced technology, all on one frame. Unlike lenses of the past, ours feature seamless, almost imperceptible transitions between different zones. Check out our lens materials, colors, and anti-glare finishes to find a product that's perfect for you. We stock an enormous selection of compatible frames that vary in shape, rim, size, and color. Find the perfect pair with us.
Author of this article:
Mark Agnew
CEO of Eyeglasses.com, which he founded in 1999. For over twenty years, he has educated consumers, improved their vision choices, and reduced costs in eyewear. Mark authored The Eyeglasses Buying Guide, the most comprehensive and best-selling glasses buying guide in the world.
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