PROGRESSIVES
Progressives and bifocals are multifocal lenses designed for patients diagnosed with presbyopia.
These lenses allow They allow these patients to see multiple focal points like distance and reading all in one lens.
Presbyopia
The gradual loss of your eyes’ ability to focus on nearby objects. It’s a natural, often annoying part of aging. Presbyopia usually becomes noticeable in your early to mid-40s and continues to worsen until around age 65.
Bifocal, Trifocal and Multifocal Lenses
There are many lense options for those correcting presbyopia. The most common selections include bifocal, trifocal and multifocal (progressive) lenses.
Bifocal Lenses
Two prescriptions for closeup and distance viewing.
Visible physical lines for segmented area.
Lined bifocals contain less distortion on the edges of your lenses.
Better peripheral vision viewing.
Trifocal Lenses
Three prescriptions for
closeup, middle and distance viewing.
Visible physical lines for segmented area.
Wider middle viewing than progressives. Less common as progressives are preferred.
More comfortable for computer use.
Progressive Lenses
Three prescriptions for
closeup, middle and distance viewing.
No visible lines! Seamless transition in between.
Bifocals and Trifocals with ‘no-line’ are considered progressives.
Progressive designs have peripheral distortion.
Example - Closeup
Example - Distance
QUICK GLOSSARY
Single Vision Lenses
These lenses have one focal point. They can be used for driving, computer use, or reading. After age 45 you may require more than one set of lenses for different visual tasks.
Bifocals
Bifocals have 2 focal points. They are typically designed for distance and reading vision. Often characterized by the visible physical lines in the lenses.
Trifocals
Trifocals have 3 focal points. They are designed for distance, middle and closeup vision. Often characterized by the visible physical lines in the lenses.
Progressives
Also known as no-line bifocals. These allow for distance, intermediate, and near vision. There are no lines in the lenses, but there are peripheral distortions in the lenses. They offer a greater range in vision but a narrower field of view.
Distortion
The design of progressive lenses will allow you to see clearly at all distances, but it also creates aberrations in the lower periphery of the lens. These aberrations will cause slight blur and distortion and are more obvious when looking far right or left especially through the bottom of the lens.
Closeup
Used for tasks like reading a book, writing a document, or using a smartphone. Also known as reading.
Middle
Used for tasks like checking out a website on a computer. Also known as intermediate.
Distance
Used for tasks like watching tv, reading a menu board and seeing the road when driving. Also known as far.
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