Have you noticed the need to hold your phone, books or restaurant menus farther from your eyes to improve their clarity?
Presbyopia is the most common reason most adults begin to wear eyeglasses. The condition generally develops overtime, beginning at around age 40, and is considered a normal part of the aging process.
Presbyopia causes an ability to focus on near objects, such as words on a page, numbers on a phone, or text on a computer. In a young eye, the flexible lens inside your eye, is able to shift focus between close objects and objects at a distance. However, as you age, this lens thickens and begins to harden— losing its flexibility and affecting your near vision.
If you already wear prescription eyeglasses for distance vision, you will likely be prescribed a pair of bifocals or multifocals to continue to see clearly at all distances.
Bifocals and multifocals for eye focusing problems
Though bifocal and multifocal lenses are typically prescribed for adults with presbyopia, in some cases these lenses may be prescribed for eye teaming or focusing problems that may cause eye strain when reading.
In these cases, the bottom segment of the lens serves to reduce the stress on the eyes by supporting the focusing skills necessary for reading.
Additionally, research shows that wearing bifocals or multifocals may help control myopia progression by reducing the stress on the focusing muscles.
What are bifocal lenses?
Bifocal lenses contain two optical powers to accommodate clear vision for both near and far.
The lens is divided into two segments, the top of the lens contains the distance vision prescription, while the bottom of the lens contains the near vision prescription. Some bifocals contain a bisecting horizontal line between the two lens powers.
Types of bifocal lenses
All bifocals lenses function in the same way. However, the lenses differ in appearance, based on the design of the segment that contains your near vision prescription.
- A half-moon/ flat-top/ straight-top/ D segment
- A round segment
- A ribbon segment– a narrow rectangular area
- Executive/ Franklin/ E style- the entire bottom half of the lens
What are trifocal lenses?
Trifocals contain three optical powers— distance, intermediate and near vision, with two segmenting lines to delineate the powers. The intermediate segment is located above the segment for near vision and is helpful for viewing objects at arm’s length, such as a computer, or car dashboard.
While trifocal lenses may be practical to those who require three different vision corrections, they are not commonly prescribed— mainly because of their unfavorable segmenting lines.
What are multifocal lenses?
Multifocal lenses are similar to bifocals, but contain multiple lens powers to provide vision at all distances— close up, intermediate, distance, and any other lens power necessary for vision clarity.
Multifocals gradually blend the lens powers together without a bisecting line, making them more attractive than bifocals. The downside of multifocals is that the clear zone for each part of the lens may be limited.
There are three different types of multifocal lenses:
- Standard progressive
- Premium progressive
- Premium personalized progressive
Standard progressive multifocals vs. premium progressive multifocals
While standard and premium progressive lenses will both provide clear vision at three distances (near, intermediate, far), the two lenses differ in the quality of improved vision, as well as affordability.
Standard progressive lenses
These lenses contain a large segment at the bottom of the lens for near vision correction. This type of lens is helpful if you have different optical prescriptions for near and distance vision, and are favorable because of the progressive transition it provides between the two viewing areas.
A disadvantage of this type of lens is that it often requires larger frames to accommodate the larger near vision segment.
Benefits of standard progressive lenses:
- Prescribed for children and adults
- Lowest cost
- Large area for near vision
- Appropriate for most prescriptions
Premium progressive lenses
Premium progressive lenses are more closely designed for your individual needs.
These lenses provide a wider viewing area and less visual distortions. These lenses can also be fitted to smaller frames.
Premium progressive lenses are recommended if you wear your eyeglasses for work, driving or full-time. However, they can be more expensive than standard progressive lenses.
Benefits of premium progressive lenses:
- Less distortions
- Wider viewing area
- Smaller frames
- Easier adaptation
- Improved vision for 3 distances
What are premium personalized progressive lenses?
These lenses are custom designed to meet all of the wearer’s individual needs.
The lenses are created based on your primary daily activities, and offer the best natural vision in all situations. Premium personalized progressive lenses provide pupil size optimization to ensure natural vision both day and night.
These lenses also offer enhanced vision through all segments of the lens, with significantly less distortions, and without the prismatic, swaying effects on the periphery of the lens.
Moreover, using special technology, near and intermediate lens segments provide the easiest adaptation, widest visual width and smoothest focus transition, without influencing distance vision.
Benefits of premium personalizes progressive lenses:
- Enhanced vision in all situations
- Improved visual comfort
- Easy adaptation to new lenses
- Fast focus transitioning
- Unlimited frame choice
Which lenses are right for me?
Each type of lens has both advantages and disadvantages. It is important to understand the differences between each lens. If you are still uncertain about which lenses to pursue, keep these important factors in mind:
1. Standard progressive lenses are a great option and at an affordable choice.
2. If you wear your glasses throughout the day or need customized lenses, premium progressive lenses are the way to go.
3. The personalized premium progressive lenses can offer an even higher quality lens with additional benefits.
Discuss with your eye doctor to determine the most appropriate option for you.
Guide to Optical Frames »