As promised in my last post about high tech eyewear, here’s my review of the emPower electronic focusing eyewear by Pixel Optics that is projected to be available in April or May . I was able to try out a prototype of the new emPower lenses at the SECO conference in Atlanta earlier this month.
These lenses are targeted at people in their late 40s and beyond that need a reading add of +1.75 D or more. At 51 years old with a 2.25 add, that fits me to a tee. The base lens is a progressive lens of low add power with an electronically activated near segment embeded in the reading portion of the lens that gives an extra +.75 D of near power when needed. With the lower base reading power, the lens claims less peripheral distortion when walking around and a wider reading area when the near power is activated compared to a traditional progressive lens.
In order to make the most realistic assessment of the optics of the emPower lenses, I put in a pair of daily disposable lenses to give me clear vision looking through the distance portion of the lens. However the trial still wasn’t an optimum test lens performance because the lenses could not be adjusted to center them at the proper pupillary distance and height like the actual lenses would be when ordered for a patient.
The representative didn’t explain how the liquid crystal technology worked but the near segment looked like a small oval with concentric rings like a Fresnel lens. I didn’t notice the rings when my friend, Leora Berns, OD, was modeling them for the photo above but they were definitely apparent when I was holding the frame in my hands.
The frames have a rechargeable battery in the temple that reportedly holds a charge for 2-3 days.
They come with an “overnight” charging station that looks pretty straight forward. I forgot to look for the battery compartment but I assume it was relatively inconspicuous since I didn’t notice it. I also forgot to ask the rep about battery life and replacement
I was dissapointed that they only had a few frames styles on display since they are supposed to have 36 styles when the line is released. Aspex, the frame company that has an exclusive contract to supply the frames for emPower, has a good reputation and the frames felt solid. The temples are somewhat bulky, presumably to hold the battery and electronics for the power activation, but the glasses weren’t unusually heavy. The liquid crystals in the near seg require that the entire near seg remain intact during the edging process so the lens shapes have to be fairly deep (tall) and the reading segment small.
OK. Enough about how they look, how well did they work?
To start off, the sales rep had to fiddle with the frame to see if it was “on” or “off”. Just a tap or brush of the temple activates it so I had to be careful to avoid accidentally activating it when I was putting the frames on. She mentioned that they were still working on the electronic interface. Looking around at things with the power “off”, my distance vision was clear and I didn’t experience any “swim” or obvious peripheral blur. I could tell when I was looking through the near seg because my vision got slightly hazy, like the contrast was decreased. I suspect that is because the ring structure of Fresnel lenses reduce optical quality somewhat. I wonder if people will be distracted by that, constantly feeling like there’s a smudge on the lenses. My near vision through the segment was clear and crisp when I activated the power boost but the increase in near power comes with a distracting “jump” of the image (that progressive lenses don’t have) when you cross in and out of the activated reading segment.
When set to “auto” mode I had to tilt my head back and forth a little more than expected to find the right tilt to activate the lens. When I struggled to get it to activate, I was again reminded that it was a prototype, not the final product. New progressive wearers often have to practice a little to learn how to use the lens, so that might be an expected part of the normal adaptation process. It also may have worked with my natural reading posture if the lenses were set to the proper height for me. Still, I suspect that you’d have to put them in manual mode when out and about trying to read things at a variety of heights and distances. For example, they would not turn on automatically if you were trying to read the price tags on a shelf or a poster on the wall because you need to tilt your head back, not down, to get the reading seg high enough to see a near object that is straight ahead.
Bottom line: For those that are very sensitive to the peripheral distortion of progressive lenses, the emPower lens does reduce that (although not to zero) along with increasing the size of the reading zone. If you could never adjust to progressive lenses, you don’t work at the computer much, you are willing to sacrifice some fashion in exchange for a high tech product and the $1000-1200 retail cost is within your reach, the emPower lens might be right for you. Personally, I’m sticking with my standard progressive lenses for general wear and my computer progressive lenses for the office.
That brings me to the biggest shortfall I see in the emPower lenses. While the technology is cool and there will, no doubt, be refinements in design that improve the electronic interface and make the frames more sleek and lighter weight, they still don’t address the main frustration of their target audience which is the inability to see things that are close, but straight ahead. Almost everyone that wears full strength multifocals find themselves tilting their head back to try to see computer screens, price tags on grocery shelves, piano music, titles of books at the library or even the faces of people they are talking to!
With the aging of the population and computer use making up an ever increasing percentage of people’s work and hobbies, this is rapidly becoming a major problem. There are specialty lenses that are designed for computer and office use but they sacrifice some distance in order to make the computer clear without having to tilt the head back. That means many patients need two pairs of glasses. Along with the added expense off multiple pairs of glasses comes the hassle of switching between the two. Meanwhile there is no good solution for jobs that require both computer and distance viewing.
In my opinion, the technology would be more valuable if it was used to add a power boost closer to the distance center of the lens to provide clear viewing at the computer. With the advanced progressive lens designs that are available now, the peripheral blur that emPower addresses isn’t a problem for most patients and those that truly need a wider reading area are probably better served by a dedicated pair of reading or computer glasses.
Putting the power boost segment near the distance center of the lens would allow most people to have one pair of glasses that covers all their vision needs. Having the segment closer to the distance virtually eliminates the risk of the liquid seg falling within the cut edge of the lens, allowing for a wider variety of lens shapes. The higher segment position would probably make it more noticeable to others and the decreased optical quality of the power segment would have to be addressed but I believe a design like that would be a revolutionary product.
While I’m not ready to embrace the current emPower lenses, it is exciting to see new technology applied to prescription eyewear. Hopefully some day (soon) they’ll come up with lenses that will let me see like I did in my thirties.