The instance you put eyewear on, they become part of your face. So it’s little wonder people focus on frame style when selecting premium sunglasses, relegating lens choices to second-tier criteria. But the purpose of sunwear is to protect your eyes and wherever possible improve your vision, a role that falls primarily on the lens, not the frame. Here are some key features to look for when shopping for sunglasses lenses, regardless of what frames you find most fetching.
This is a much abused term in eyewear marketing, often applied to lenses that are scarcely better than cellophane. What “optically correct” ought to refer to a lens that is tapered and de-centered, meaning it is thicker directly over the eye (which is not the geometric center of the lens) and gradually becomes thinner towards the edge. This allows the eye to focus comfortably and with equal clarity in all directions. Inexpensive lenses are often made in a constant thickness, which requires the eye to work harder to maintain focus.
Sunglasses are often called “dark glasses,” and with good reason: they’re made to dramatically diminish the amount of light that reaches the eye. But your eyes struggle to accurately identify colors in low light conditions, which can result in a loss of vital information. Color recognition can be restored, however, by altering the lens chemistry so primary colors appear brighter. 7eye uses Amplified Color Technology in all of our Re-ACT NXT® lenses so you can see all 7 colors of the visible spectrum in vivid detail.
The popularity of photochromic lenses is due to their seemingly magical ability to automatically darken in sunlight and fade to clear indoors. There are two issues to weigh when evaluating photochromic lenses: how quickly do they change from clear to dark and back again, and how long will their photochromic properties last? With 7eye’s 24:7 NXT Contrast lenses, the lenses reach 90% of their darkness within 30 seconds of exposure to UV and fade quickly too. And because they’re made in NXT, they’ll keep this capability for up to four times longer than many non-prescription polycarbonate photochromic lenses.
Probably the most-recognized term in sunwear, polarization serves a very specific function: to filter out reflected light bouncing off non-metallic surfaces. For all practical purposes, this non-metallic surface is water, which is why virtually all lenses recommended for use on or around water are polarized. By eliminating reflected glare, polarized filters allow fishermen to see through the water’s surface. The ability to see underwater features is an indispensable edge for the angler, but away from the water polarization isn’t always an advantage. Display panels can be hard to read and for motorcyclists the inability to detect glare on the road could be hazardous.