Solar-powered sunglasses: POC Aspire Solar Switch review
POC’s latest eyewear innovation incorporates a solar-powered liquid crystal panel in the lens that instantly darkens or lightens depending on the conditions. It’s a super slick idea, and the technology is truly ingenious given there are no batteries required. However, while the concept holds a lot of promise, the real-world delivery has a little ways to go yet.
One lens to rule them all
Eyewear companies have long been chasing the idea of a single lens that could work in a very wide range of conditions. Photochromic options have been nice in that they’re offered in a good selection of tint colors and visible light transmission (VLT) ratings, and they’re relatively inexpensive (especially as compared to buying multiple individual lenses). However, despite some progress in the technology, they’re still relatively slow to adjust, especially when moving from brighter to darker conditions (which, ironically, is often when you need that transition speed the most).
More recently, some brands have begun playing with electrochromic setups, using an embedded liquid crystal panel in the lens (kind of like what you’d find in a monochrome GPS cycling computer screen). These are far more responsive, instantly lightening or darkening depending on how much power is applied to the film. But these aren’t a panacea, either: they require electricity to operate (usually in the form of rechargeable batteries), they tend to be a bit bulky and heavy, and there are more limitations in terms of tints.
POC’s new Aspire Solar Switch takes the electrochromic idea and turns it up another notch. The basic concept is the same, but in this case, the power comes from seven tiny solar panels that are built into the upper edge of the lens instead of a standalone battery.
Moreover, the design is particularly elegant in that it also uses the photovoltaic cells as light sensors. In brighter conditions, there’s automatically more light hitting the cells and more power generated as a result, which progressively darkens the lens. But when there’s less sunlight on the cells, there’s automatically less power produced, the liquid crystal film relaxes, and the whole lens allows more light to pass through.
POC packages all of this into its Aspire frame design, which features a Zeiss-certified cylindrical shield-type lens, a full-circumference frame, and hydrophilic contact points at the temples and nose for a non-slip fit. The ends of the temples and the nosepiece are also adjustable for fine-tuning how they sit on your face.
POC offers the Aspire Solar Switch in a single color configuration that includes a black frame and a greyish/brownish lens tint with a mirror coating. Retail price is US$400 / £340 / €380 / AU$TBC, and actual weight for my sample is a pretty hefty 50 grams — only about 10 grams heavier than a standard Aspire Clarity, but almost twice as heavy as something more barebones like an Oakley EVZero.
Great on paper
The concept behind the Aspire Solar Switch is brilliant, and the lens adjusts instantaneously, just as promised. The total range is well suited for riding in bright, sunlit conditions interspersed with patches of shade when you might otherwise be struggling a bit to make out details in the road. In the lighter mode, VLT is a modest 15% (or “Category 3” by European rating conventions); in the darker mode, it’s just 8%, or Category 4.
There’s not a whole lot of contrast on tap, though — certainly nothing like what you get from Oakley’s Prizm or Smith’s ChromaPop lenses, for example — but the convenience of that fast-changing lens tint might be enough to win some people over, anyway.
Overall coverage is very good, too, as I’ve come to expect from POC’s road-oriented eyewear. My preferred head-down position puts the upper edge of the frame somewhat in my field of view, but I still found it to be generally inoffensive. Similarly, the generous coverage down below and off to the sides does a good job of blocking oncoming air (which would otherwise dry out my contact lenses).
In terms of fogging, I wouldn’t say that the Aspire Solar Switch was particularly better or worse than other full-framed sunglass I’ve used in years past. They do seem more prone to fogging than rimless or partial-frame sunglasses, but it’s not terrible.
At a full 15 cm in width, the overall fit seems better suited to those with bigger and/or wider heads. I was able to adjust the three-point fit well enough for my smaller-sized noggin, but the wider spacing of the temples still pushed the tops of my ears down a bit. Nevertheless, there’s an ample range of adjustments on the nosepiece and temples, so I suspect most users would be able to get these work. From a general aesthetic perspective, though, they’re pretty massive.
And then the novelty wears off
Sounds like all is good, then, right? Not so fast. Unfortunately, there are some major quirks associated with that fancy lens.
POC bills the Aspire Solar Switch as being able to “instantly change tint based on light conditions.” However, my experience was that the lens activation depended much more on whether the sun’s rays were directly hitting the solar cells, not the ambient lighting conditions in general.
On one ride in particular, it was extremely sunny outside, but the lens wouldn’t noticeably darken until I actually turned my head to face the sun. Essentially, my own head was providing shade for the solar cells. As far as I could tell, the cells weren’t generating enough electricity in that position, so the film wasn’t activated and the lens remained stuck in its lighter setting despite the fact that the general conditions were very bright.
“The main objective is to remove the strongest solar beams and avoid blinding the user, so it is trimmed to activate super-fast when exposed to direct solar light, switching instantly,” explained Damian Phillips, POC’s head of PR and communications. “However, the technology changes the tint in a way which is linear to the light intensity — i.e. more light, the darker it gets, but sometimes the eye/user will not notice or see that change.
“There will be a difference in max tint when it is blue sky and direct sun compared to the max tint when it is cloudy and the solar energy is lower. The sensors create more energy for the LCD when there is more sun, so the LCD lets through less light the more energy it gets.”
Fair enough, but while the total light transmission might change continuously, the color of the tint changes as well. By definition, the type of liquid crystal films used in electrochromic eyewear can only switch between almost-clear and varying shades of grey. However, the base tint of the polycarbonate lens on the Aspire Solar Switch has a slight brownish hue to it. In most situations, it’s not a big deal. But when quickly moving back and forth between direct sunlight and shadows, that rapid-fire change in tint (and, therefore, contrast) can be pretty distracting.
“That is an intentional side effect,” Phillips said. “The change in tint is actually a change in color of the LCD, when activated, which is grayish compared to its clear base lens. We could theoretically combine the LCD with a grey base tint, but that would darken the starting VLT and we believe that the best performance and safety come from starting with as low a VLT as possible.”
Intentional or not, I can’t say I was a fan.
Overall optical quality of the lens left a lot to be desired, too.
Generally speaking, I’ve been very satisfied with the different models of POC eyewear I’ve used to date, all of which have offered excellent clarity and minimal distortion — perhaps a reflection of that heralded Zeiss certification. However, my guess is that the Zeiss certification on the Aspire Solar Switch is earned before the liquid crystal panel is added.
Peering through the Aspire Solar Switch is almost akin to looking through a pair of premium cycling eyewear with a layer of plastic food wrap applied on top. The quality of vision I experienced depended somewhat on what portion of the lens I was looking through, and there was almost enough distortion to give me a headache. The inner surface of the multi-layer lens is also shockingly prone to scratching — don’t you even think about trying to wipe the lens with anything other than the included storage bag (which had better be super clean).
Phillips implicitly acknowledged the degradation in optical quality, but suggests the advantage provided by the Solar Switch technology makes for a worthwhile trade-off.
“Incorporating LCD technology into a lens naturally leads to some changes/differences in optical properties when compared to our regular lenses,” he said, “but the Solar Switch lenses are still certified to optical standards and come with the benefit of instant VLT changes.”
Lots of sizzle, but the steak is a little chewy
Overall, I’d have to say the POC Aspire Solar Switch electrochromic sunglasses were pretty disappointing, especially given how high my hopes were for these things going into the test.
The concept behind them is truly ingenious, the potential of the technology is extremely promising, and I’d even argue that they look pretty good, too. But at least in this iteration, the end product falls well short of my expectations.