It has been one year since I started wearing the Varilux X design, and after a full 365 days of wear, and comparing against older, existing technology, as well as one or two new products, I wanted to update the pros and cons of this quantitatively different progressive lens…
After wearing this lens design for a full year I am happy to report that it is definitely the most comfortable progressive I have worn. It provides an exceptional balance between near and distance needs, allowing for a wider-than-normal mid-range zone and a great depth of field than I have ever experienced in a progressive. The X in the name comes from Generation X and this lens truly delivers for my generation and our unique digital needs.
For the typical work/lifestyle environment it’s hard to beat this lens…
The Less Good
I’m gonna drift into the finer details of lens design concepts here, so please forgive me if I go too fast…
Progressive lenses can be categorized generally into two groups: fixed corridor and variable corridor designs
What’s a Corridor???
In the context of a spectacle lens, the corridor is the channel through which the lens changes power from your distance correction to your near correction. Historically, almost all lenses were what we called a fixed corridor. This means that no matter how the frame fit on your face–or how high your eyes were away from the bottom of the frame–the distance (in millimeters) from the distance zone to the near zone was always the same. The advantage to this type of design is two-fold. First, it allows the lens design to guarantee a certain amount of space for the mid-range distance. Secondly, in the older analog technologies it made the math of the design better control the experience of the peripheral distortion (which as you may recall from my previous post here is unavoidable).
The disadvantage of a fixed corridor, however, is if your segment height too short, then the full power of your reading correction is cut out of the frame and you never get to read comfortably. Conversely, if your frame is extra large, you can experience dramatic distortion below your reading zone (just imagine trying to look at your feet while looking through complete, wavy blur).
To deal with these challenging fits, especially as lens technologies were improving and the cosmetics of frames were changing towards much smaller frames (remember all those small rectangular looks in the early 2000’s?), the variable corridor lens was developed.
Variable corridor lenses allow us to compress the amount of space given to the intermediate zone, so you can still reach the full near correction in a small frame. It also allows us to to give more space to the mid-range, if the frame is exceptionally large, thereby also eliminating the messy distortion below your reading area in a big frame.
Both lens design styles have their advantages and disadvantages. The right choice can depend greatly on the underlying technology and the frame fit you choose with your optician.
If there is a flaw in the Varilux X Design, I might say that since it is exclusively a variable corridor length, if you have an unusually long segment height (typically this might happen for an Asian fit in a larger, modern frame) the reading area can be too low to be practical or functional. In these relatively rare circumstances I feel the X Design is not the best choice for a patient.
I discovered this issue through troubleshooting negative experiences with the X Design. In each case, when I switched to a fixed corridor length design, the problem was resolved.
After a full year of wearing this lens, I don’t know if I could say there is a “bad” for this lens. There are caveats for unusual fit or lifestyle needs, but this lens is far and away the easiest to adapt to lens I’ve encountered. There are other lens technologies that work very well, and a couple of new products I’ll be detailing very soon. But of the 62 progressive lens designs I have personally worn, this lens delivers the best balance of function at all viewing distances, and just as important it seems to work well for all prescription types.
Now if they could just make it offered in the new Transitions Colors (article coming within days!) and Polarized Green…hopefully I’ll get to do ANOTHER review update after these new lens styles become available in the Varilux X Design!