Sunglasses are an essential piece of gear for people who enjoy spending time outdoors. A good pair of performance sunglasses can cut road glare on a 50-mile bike ride, shed water when you're throwing a splitwheel in your kayak, and may even enhance optical clarity to help you better read the putting green.
Not sure where to start when it comes to choosing a new pair of shades? On the fence about polarized lenses or unsure what frame style will best suit your face? Don’t worry. This guide is designed to help you learn everything you need to know about sunglasses. Although we’ll be focusing primarily on performance eyewear, you can apply many of the principles covered in this guide when selecting a pair of fashion sunglasses, too.
Categorized as either UVA or UVB, these invisible ultraviolet light rays from the sun can cause serious damage to your eyes and lead to the development of cataracts, macular degeneration or even permanent retinal impairment. Sunglasses with a 100% UV protection rating will safeguard your eyes against both UVA and UVB rays. You may also see sunglasses labeled as “UV 400.” These block light rays with wavelengths up to 400 nanometers. In plain English, this means that even the tiniest UVA and UVB rays are prevented from ever meeting your eyes. Remember, UV rays are all around us during daylight hours, even on cloudy days.
Although fit is a big consideration, the most important element of your sunglasses is undoubtedly the lenses. Sunglass lenses are made from either composite or glass, and each has some advantages and disadvantages.
These are lighter than glass lenses, but are more prone to scratching. They do, however, offer more shatter resistance than glass. Composite lenses are typically made from a polycarbonate material. Polycarbonate lenses are extremely light and nearly shatterproof, making them good for impact protection. Although most lenses will be labeled simply as “polycarbonate,” you may find some labeled “CR-39.” These lenses are lighter than ordinary composite lenses, scratch-resistant and provide 100% UV protection.
These lenses offer the best optical clarity and scratch resistance, but are heavier than composite lenses. They can also shatter or break on impact.
Ground and polished to ensure that they are free of distortion.
Generally the toughest and most shatterproof. Polycarbonate is scratch-resistant, lighter, and more impact-resistant than glass.
Ideal for water sports, cycling and driving. Light striking flat surfaces such as water, snow, glass and pavement can be reflected into your eyes. Because of the angle of reflection, this glare is more intense than normal sunlight, irritating your eyes and inhibiting your vision. Polarized lenses reflected block glare with a special film that incorporates horizontally aligned micro crystals, which work similar to shutters in a window.
Also called photochromatic lenses, these incorporate a light-sensitive layer within the lens that actually darkens when exposed to sunlight and lightens as conditions grow darker.
Tinted from the top down, making the top of the lens the darkest. Gradient lenses can be made of composite or glass. They are a great choice for driving because they cut the glare from the sun without diminishing your view of the dashboard.
Lens color plays an important role in the performance of your sunglasses. You should choose a color based on the way your eye reacts to it. Different colors can cause different visual sensations in different people, so choosing your lens color is a very personal decision. In other words, if you really like grey lenses, you might not like switching to brown, and visa versa. To give you a better idea of what to expect, we’ll cover some of the basic characteristics of each lens color.
Now that you've chosen the color of your lenses, you'll need a frame to hold them. Sunglass frames are generally made from composite, nylon, metal or an alloy.
Frames made of nylon are created using the same polymer used to make nylon fabric, although in a form that is more similar to molded plastic. Nylon frames are lightweight and relatively flexible. This allows the frame to bend slightly and return to its original shape, which makes nylon a good choice for high-performance eyewear.
Plastic, also called thermoplastic or composite, is a lightweight, strong, flexible and inexpensive material for creating sunglasses. Although not as strong as nylon, high-quality plastics used to create sunglasses are still quite durable.
Heavier and more rigid than polymer frames, metal frames are slightly more prone to bending or breaking at stress points. However, because metal frames are more rigid, many models have spring-loaded hinges to help them stay in place and provide a flexible fit. The ends of the ear pieces and the bridge over the nose often have rubber grips attached for comfort. Metal frames are general more suited toward casual wear.
The popularity of outdoor sports like mountain biking, rock climbing, kayaking, skiing, golfing and fishing has created the demand for performance-oriented sunglasses. To meet the various demands of both recreational and competitive athletes, sunglass manufacturers are producing lightweight and flexible sunglasses made of durable materials featuring grip components and high-tech performance lenses.
Optical quality and visual clarity are the most important aspects of good sport sunglasses. For this reason, polycarbonate lenses are the most widely used. Glare-blocking polarized lenses are also very in many outdoor sports.
Glass lenses are used occasionally in sports sunglasses because of their excellent optical quality. However, many people involved in more extreme sports shy away from them because of the potential for shattering. Glass lenses are appropriate for low intensity activities like golf, which emphasizes visual acuity.
Face shapes are categorized into five types: square, round, triangular, oblong and oval. Follow these guidelines to help you select the frame that will best complement your features.
Look for frames that are curved slightly. The top of the frames should sit high enough on your face to downplay your stronger jaw line.
To offset a predominantly round face, look for frames with straight or angular lines. Frames in a darker color also minimize fullness.
A triangular face is characterized by a broader forehead with a narrower mouth and chin. Frames with a thin rim and straight vertical lines will help balance out a triangular face. Make sure that the frames don't sit too high on your face or they will exaggerate the shape. Large frames, bold colors and square shapes should be avoided on triangular faces.
Oblong faces are longer than they are wide and close to the same width across the forehead, jaw line and cheekbones. Most frames look good on oblong faces, as long as the size of the frames is in proportion to the rest of your face.
An accurate temple measurement will ensure that the frames will sit comfortably on your face without sliding down your nose or rubbing behind your ears. Since manufacturers offer slightly different temple sizes on select models of frames, we recommend you use the following guidelines to get an idea of the size you need. (Note that the temple-to-temple measurements will be included in the product details online.)
Temple length is measured in inches across the top of the frame, from one hinge point to the other. The temple sizes below correspond to the type of fit they provide.