A surprising number of people are wearing reading glasses on a chain because a varifocal did not work for them in 2012. That is a reasonable conclusion from the evidence they had. It is also out of date, and it is worth knowing which parts have moved and which parts never will.
What a varifocal is actually doing
A progressive lens changes power gradually down its surface: distance at the top, intermediate through the middle, reading at the bottom. Because that change has to happen somewhere, there are regions either side of the corridor where the optics are compromised. That is not a manufacturing flaw — it is the geometry of putting three prescriptions on one surface, and no design will ever remove it entirely.
What has genuinely improved
- Free-form surfacing — lenses are now calculated and cut individually rather than pulled from a set of moulded semi-finished blanks, so the design can account for your actual prescription rather than a nearest match
- Wider corridors at the intermediate distance, which is the range most modern life happens at
- Position-of-wear calculation — the design can be adjusted for how your frame sits on your face, where the design accepts those values
- Frame-shape optimisation, so the lens is calculated for the actual shape you chose rather than a generic round blank
- Shorter corridors that fit the shallower frames people actually want to wear
- Better coatings, which matter more than people expect at night and on screens
What has not changed
There is still a trade-off between the width of the clear area and the speed of the transition. A lens with a very short corridor, to fit a shallow frame, concentrates the change into less vertical space, and that makes the peripheral distortion more noticeable. Anyone who tells you a varifocal has no soft edges is describing a lens that does not exist.
Why two people get different results from the same lens
Far more of the outcome sits in the dispensing than in the product. Fitting height, monocular pupillary distances, the depth of the frame and the tilt it sits at all decide where the corridor lands relative to your eye. The same lens design, measured properly in a suitable frame, is a different experience from the same design in a frame that is 4 mm too shallow. We go through this in what a proper fit involves.
If you failed with varifocals before
It is worth bringing the old pair in. We can measure what you were actually given — the design, the fitting height, where the corridor sat — and that usually explains what went wrong far more precisely than memory does. Sometimes the answer is a different design. Sometimes it is a deeper frame. Occasionally it is that a varifocal genuinely is not the right answer for how you use your eyes, and a dedicated pair for one task is better; we would rather tell you that than sell you the same disappointment twice.
Who they suit least well
People who spend most of the day at a fixed intermediate distance — two monitors, a workbench, a sewing machine — often do better with a lens designed around that distance and a separate pair for driving. A varifocal is a compromise optimised across your whole day; where your day is mostly one thing, a dedicated design usually beats the compromise. More on that in the second pair worth owning.
The question is not whether varifocals work. It is whether this varifocal, in this frame, measured this way, works for your day.← Back to the Journal
