Photochromic lenses, which darken and lighten based on available light, have been around for years and I love them鈥攎ostly. They are an excellent alternative to cumbersome interchangeable-lens systems, but the major drawback has been slow transitions that can leave you blind as you wait for the lenses to adjust.
Uvex, which already made some of the best transition lenses聽on the market, has solved this problem with its聽. These cycling shades use e-tint technology, which allows the lenses to instantly toggle between 16- and 64-percent light transmission with the press of a button.
The shift comes courtesy of a thin, liquid crystal film聽sandwiched between two polycarbonate lenses. With the input of a low-voltage electrical current, by way of a built-in battery, the crystals in the film shift position to block more or less light. Ohio-based AlphaMicron developed the system for military use, and Uvex subsequently licensed the technology for its shades.聽
A micro-USB port is located directly behind the power button for charging. The lithium-ion battery takes only a few hours to fully charge and is said to last for up to 50 hours. However, since the battery trickles when the lenses are darkened, it鈥檚 important to store them in their 鈥渃lear鈥 mode. I made the mistake of leaving the glasses dark after a ride one evening and came back to find聽them dead (and light) the next morning.
If you鈥檙e like us, you鈥檙e probably thinking batteries and electronics in a pair of shades will make them heavy, unwieldy, and totally dorky. But the lithium-ion battery fits inside a very trim temple and聽the rubberized, match-head size toggle switch is barely noticeable. Overall,聽the Variotronic S glasses look like any other wrap-style fitness shields on the market. There鈥檚 also a full-frame version (the ). And, truthfully, the orange-and-white colorways of both are good looking (in a German sort of way).
All of this might sound a bit ridiculous and RoboCop, but after a few months of riding in the Variotronics, they are the only shades I find myself reaching for. In early morning or late afternoon, photochromic lenses are optimal because they mean you won鈥檛 get caught with glasses for聽the wrong light. And the ability to toggle between lenses instantaneously鈥擴vex says 1/10th of a second, though I have no way of verifying that except to say it鈥檚 immediate鈥攎eans that going in and out of tunnels (road) or dark woods (MTB) is safer and easier than ever.
The Variotronics are not perfect. For one, I鈥檇 prefer it if the lenses dropped all the way to zero percent light transmission (rather than 16). As it is, they are useable after dark, but not ideal. If they went to full clear, you could even ride in them at night. The optimal scenario would be to have a three-stage transition, with the existing two light settings plus a third, zero-tint option.
Also, the lenses are polarized, so clouds, water, and other reflective surfaces render in a strange, 3-D sort of way. It can be distracting while riding, and I鈥檇 frankly rather Uvex just drop the polarization, which isn't so necessary for cyclists.
There鈥檚 also the hassle of having to charge your glasses (and the nuisance of dead lenses in case you leave them on). This can be problematic, but it鈥檚 also true that the convenience of basically wearing two sets of glasses in one may outweigh the inconvenience.
The bottom line? I鈥檝e happily worn photochromic lenses for years but always wished that there were a way to make the transition faster. Uvex has answered that wish, and the result is the most advanced glasses on the market鈥攂oth in terms of technology and performance. At $350, the price of entry is steep. But I鈥檓 sure the technology will continue to advance, with longer battery life and varying light transmissions, and the prices will drop. If you want a pair of do-it-all glasses聽that are light, rugged, and have built-in dual-tint lenses today, there鈥檚 simply nothing out there like the Variotronics.