Bifocal lenses: what they are, how they work and how they differ from progressives
Bifocal lenses have two zones, distance and near, separated by a line. How they work, when they still make sense, how they differ from progressives and from two pairs of glasses, and which frame to choose.
Two distances, one lens, a line in between.
The bifocal lens is the oldest answer to a problem everyone over forty knows: seeing clearly both far and near. Today most people choose progressives, but bifocals still make sense in some specific cases. Here is how they work, what sets them apart from progressives and from two pairs of glasses, and which frame they need.
zones in the same lens: distance at the top, near at the bottom
visible line between the two zones: the sign that tells it apart from a progressive
intermediate zones: the distance of the monitor and the dashboard is missing
How a bifocal lens works
The upper part of the lens carries the distance correction. In the lower part there is a segment with the near correction: you look through it by lowering your eyes, as when reading. The two zones are separated by a sharp line, which is visible on the lens and which, when you pass from one zone to the other, produces a small jump in the image.
Bifocals or progressives: the differences
A progressive lens moves from distance to near gradually, with no line, and has a zone in the middle for intermediate distances: the computer screen, the dashboard, a shop counter. A bifocal does not: it is either distance or near. In exchange it has a wide, stable near zone, without the blurred side areas typical of progressives, and it needs no adaptation.
- Bifocal: visible line, image jump, no intermediate distance, wide near zone, no adaptation period.
- Progressive: no line, all distances, narrower near zone, a few days to get used to. The full guide: progressive lenses, how they work and which to choose.
Progressive lenses or two pairs of glasses?
Two pairs, one for distance and one for reading, give each distance the widest and simplest lens. The price is the gesture: taking the glasses off and putting them on every time your gaze changes distance. For people who read a lot and drive little, they can be enough; for people who switch between far and near all day, progressives are more comfortable. The bifocal sits in between: a single pair, without the intermediate distance.
When bifocals still make sense
For people who have never got used to progressives, for people who do a lot of close work and want a wide reading field, and for people who have worn bifocals for years and are happy with them. For computer work it is also worth considering office lenses, designed for near and intermediate distances.
The right frame
Bifocals and progressives need vertical space: the lens has to hold both the distance zone and the near zone. Very low, narrow frames cut off the near zone. Better to choose fronts with a lens of good height: aviator, panto, square and rectangular shapes that are not too low. Fitting measurements are taken with the frame on, which is why bifocals and progressives are fitted in our boutique in Crema. How buying a frame online for prescription lenses works: frame online, prescription lenses.
Four frames with a tall lens
AHLEM Carpentier Smokedlight
The acetate aviator by AHLEM, optical version: the shape with the most room in the lower part of the lens, where the near zone sits.
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AKONI Atlas Brushed Silver
A wide single-rim titanium navigator, handmade in Japan: a large, light lens, comfortable for people who wear glasses all day.
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Lesca Lunetier Heri LTD32 Cognac
The panto by Lesca in a cognac edition: the lens widens towards the bottom, the shape that has always gone with reading lenses.
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EYEVAN 7285 1158 820
The rounded-corner rectangle inspired by the screens of the Seventies: a full shape that does not cut off the lower part of the lens.
View productMore lens guides
Progressive lenses · Computer glasses · Lens thickness · Photochromic lenses · How to read glasses measurements
What are bifocal lenses?
Lenses with two corrections in the same lens: distance at the top, and at the bottom a segment with the near correction. The two zones are separated by a visible line.
What is the difference between bifocal and progressive lenses?
A progressive moves from distance to near gradually, with no line, and has a zone for intermediate distances. A bifocal has only two zones separated by a line, with a small image jump, but a wider near zone and no adaptation.
Progressive lenses or two pairs of glasses?
Two pairs give the widest lens for each distance but have to be swapped every time. Progressives cover all distances with a single pair. For people who often switch between far and near, progressives are more comfortable; for people who read a lot and drive little, two pairs can be enough.
Which frame should I choose for bifocal lenses?
A frame with a lens of good height, because it has to hold the distance zone and the near segment: aviator, panto, square and rectangular shapes that are not too low. Very low, narrow frames cut off the near zone.
Can bifocal lenses be ordered online?
No: bifocals and progressives require measurements taken with the frame on. Online you can choose the frame; the lenses are fitted in our boutique in Crema.
Distance, near, or both
In our boutique in Crema we test your eyes and take your measurements with the frame on, and tell you whether bifocals, progressives, office lenses or two pairs work best for you. Online, message us on WhatsApp.