Summer may (sadly) be over but the dangerous UV rays of the sun still shine strongly and keeping your eyes safe on those sunny days of fall is still important. But in the search to score a cool new pair of shades we always forget that they shield our eyes from their most important work. Because no matter how flexible the colors, soaking up the sun at the detriment of your skin is never a good look to walk around. Therefore it is important to know what you are buying. But, like most technically embedded products, there’s a lot of technological jargon to tackle to truly appreciate what’s going into a couple of sunglasses. Read on as we dissect the most relevant words to use when searching for shades, from lens tints to frame fabrics and filter types.
Lens Technologies. One of the few words most people know about sunlasses is UV (short for ultraviolet) rays – that is, the radiation that comes from the sun and affects our eyes. Nearly all sunlasses now provide complete protection against UV rays, but what you should look for in your shades is what is known as the ‘safety index.’ The safety index, rated from zero to four, refers to the filtering capabilities of a lens and shows how much light a sunglass lens lets through (if you went to get very technical, this is known as visible light transmission or “VLT”). Grade zero is a clear or mildly tinted lens with 80-100 percent VLT, while grade four is just 3-8 percent VLT for a very dark lens. Look for those with a protective index from one to three to be protected when trying to cop shades for daily use.
Lens Treatments. In addition to the protective index, there are other lens treatments that influence the appearance of a lens, as well as its level of protection. Polarization – consider those shades of Oakley sport – is the most popular technology produced by applying a polarized film to the actual lens. That helps to block the sun’s glare, keeping your vision sharp and clear even in bright sunlight situations. Taking it one step further, the photochromic lenses respond according to sunlight intensity. Then there are photo-polar lenses that are a mixture of photochromic and polarized lenses so that they block the glare and respond to shifting sunlight. At last, the lenses are mirrored. These feature a mirror coating on the surface of the lens (also known as a flash coating) that gives a one-way mirroring effect. This reflects the sunlight that reaches the lens surface and prevents it from touching your eye.
Lens Colors. Complete colored lenses were on everybody’s mind this summer but it’s worth understanding that various colored lenses also have different advantages before you go copping a pair depending on whether the color suits you ‘re wearing. As with Instagram filters, the tint of a lens can also shift the overall mood of our outlook. Blue lenses enhance color perception and help identify the contours of objects to what you may expect. On the other hand, green lenses add warm colors to what you see, and increase contrast, which helps to minimize eye strain. Yellow and brown lenses are the perfect way to assess the sense of depth and they also help you see red and green tones while minimizing blue light. If you want to see the world in its most authentic form, select gray lenses as they have the truest perception of colour. Lenses can be full color or have a gradient effect. The fading look is not only about beauty but also has advantages for your eyes as it makes it easier to see in different light conditions.
Lens Materials. Lenses are usually either made of glass or plastic. Glass lenses give the clearest vision and they also have a greater resistance to scratching, but they weigh more and can shatter if you drop them hard enough. Usually, plastic lenses are made of either polyamide, polycarbonate or CR-39 material. Polycarbonate is the lightest plastics and the most resistant alternative to crystal glass, whereas polyamide typically offers the highest quality of vision. CR-39 is the most commonly used material and the go-to for polarized lenses.
Frame Materials. Now you have the lens jargon down, the next aspect of your shades that you need to learn is the structure. Broadly speaking, most sunglasses are either made of aluminum, nylon fibre, or acetate. Wood is also becoming more common as it is a natural resource and can be grown sustainably.