Learn About Multifocal & Bifocal Contact Lenses

20.07.2023 | Leah | TTDeye Care

It should be known that contact lenses have been around for decades now. However, the technology that makes the operation of these lenses possible is changing consistently. The lenses that you'd find nowadays are miles apart from what you had commonly found years before and even today, manufacturers are looking into making these lenses more advanced so that their overall sales could increase. As of the current day & age, there are mainly two types of contact lenses that you can find for everyday consumers: bifocal & multifocal contact lenses. Thus, we’re going to discuss these two in detail and help you make a well-informed purchase.


What Do You Mean By Bifocal & Multifocal Contact Lenses? 

In simple terms, bifocal contact lenses are described by two separate or distinct segments for providing power for different types of vision. For instance, the upper half of the contact lens will be used for distance vision while the lower half for near vision. With the help of bifocal contact lenses, you'll be able to change your focus from far to close and vice versa at any required time. Nevertheless, your vision will not be apparent between the segmented parts. 

On the other hand, multifocal contact lenses are defined as any type of lens that has more than one vision power, including trifocals, bifocals, and even progressive lenses as well. With the help of multifocal contact lenses, you'll be able to view in any type of direction you'd want, with almost a similar kind of vision. Such contact lenses provide you with immense power over reading glasses.

Therefore, if we're going to describe both of them, then it can be said that bifocals only have two types of vision power whereas multifocal contact lenses are an umbrella term for all types of contact lenses that have more than one kind of visual strength. Bifocal contact lenses are a part of multifocal contact lenses.


How Do Multifocal Contact Lenses Work?

 Depending on the overall design of the lenses, different bifocal as well as multifocal contact lenses work in various ways. The following are some of the significant design elements that they fall under:

  • Vision Designs That Are Segmented - These are mainly multifocal lenses that are rigid and are also gas permeable whose design resembles almost like the trifocal and bifocal eyeglasses. The lower part of these lenses contains the ability to magnify nearby objects while the center and the topmost part are used for viewing distant objects. These types of designs are also known as translating or alternating designs.
  • Vision Designs That Are Simultaneous - These are those types of multifocal lenses that have designated specific regions on the lenses through which near and far-off visions can be obtained. It all depends on the kind of object that the user is trying to view, and he or she can use that part of the lens that helps in providing the sharpest vision available. Simultaneous vision designs come in two forms - aspheric and concentric. 

 


Knowing The Differences Between Aspheric & Concentric Multifocal Contact Lenses

1. Aspheric Multifocal Contact Lenses

The overall design of these types of lenses can be felt similar to the design of the progressive eyeglass lenses. There will be a gradual change in vision power for viewing distant and nearby objects without any visible lines in the current lens. Since these are simultaneous vision lenses, you must be trained enough or have enough learning to use the proper power of the lens at the right moment.

2. Concentric Multifocal Contact Lenses

Concentric multifocal contact lenses are those multifocal lenses that contain the vision power to see distant objects in the middle or center of the lens - which is then surrounded by concentrated rings of distant and nearby vision powers according to your bifocal contact lens requirements.

It should be noted that at least two concentric rings of power vision are present around your pupil (in normal light conditions). But, as your pupil constricts and dilates according to the power source, that radius area might change. Usually, these lenses are made from rigid or soft gas-permeable contact lens materials.


Knowing About Segmented Bifocal Contact Lenses

 When it comes to the functioning of a segmented bifocal contact lens, they work much like regular bifocal contact lenses. They are made from rigid gas permeable materials and have different power vision segments which are separated by a line.

As usual, the topmost section would be for distant vision while the lower for nearby vision and your eye will have the capability to see through either one of them - depending on your requirements.


Should Bifocal Contact Lenses Work for You?

 Bifocal contact lenses have been around for quite some time now and only recently have gained popularity. The good thing about technology is that if something doesn’t fit you right, you can always pick another option. According to your condition, you can try any one of the following two options:

  •     Modified Monovision which uses a multifocal lens on one eye and a single-focal lens on the other.
  •     Regular Monovision uses single-focal lenses on both eyes - where one is used for distant objects and the other for nearby purposes.

However, if the above two options don't work out for you, then you can opt for regular eyeglasses with progressive lenses in them. It should be noted that progressive lenses can help in correcting some amount of astigmatism or any refractive error - which will be unavailable if you use contact lenses. Such glasses can provide you with sharper vision, including when night-time driving. 


Final Words

Your eyes are an essential part of your human body, and taking care of them correctly is what counts the most. With the data mentioned above, you can easily interpret the differences between the two types of contact lenses and thereby choose the one which suits you the best. Just ensure the brand or manufacturer you're choosing has good reviews, and you'll be fine.