Sunglasses 101

Some sunglass basics.

Do I really need to wear sunglasses? Yes. Not only are they fashionable, but they protect your eyes from harmful UVA and UVB rays. Ultraviolet light is invisible to the eyes, but over time can cause cataracts, macular degeneration and even permanent blindness. In other words, UV is bad for your health. In the same way that sunscreen protects your skin, sunglasses are the best way to protect your eyes. Remember, UV rays penetrate even on cloudy days!

What different materials are sunglasses made from? Most high end sunglasses are made from nylon, metal, or plastic. Nylon frames are a popular choice, as they are durable, resistant to UV damage, and light weight. Most metal framed sunglasses are made from some type of metal alloy. Metal frames are extremely rigid and are generally not used for sports related activities. Basic plastic frames tend to be found on low-end sunglasses but they are not as comfortable or durable as other frame materials.

What type of frame should I choose? Let's take a look at the three most common styles: full frame, half frame, and frameless. Depending on your particular use, each frame can have a different purpose. Full frame sunglasses completely surround the lens and are the basic choice in both fashion and sport sunglasses. Half frame sunglasses surround half of the lens and are ideal for many sports and outdoor activities because they typically weigh less and offer interchangeable lens options. Frameless sunglasses are the most uncommon style because the hinge and earpieces are attached directly to the lenses. If you want the lightest shades possible, frameless is the best option.

What is the best lens material and what are the main differences? There are three basic lens materials: plastic, polycarbonate, and glass. Plastic lenses are lightweight, tint easily, and are more shatter resistant than glass lenses. In addition, plastic lenses tend to be thicker than polycarbonate lenses and usually require special scratch-resistant and UV coatings to increase durability. Polycarbonate lenses are very lightweight, block 100% of UV rays naturally, and are 10 times more impact resistant than regular plastic or glass lenses. This makes polycarbonate lenses one of the most popular choices. Glass lenses offer the best optical clarity and exceptional scratch resistance but are a bit heavier and more expensive.

What types of lens coatings are available? Coatings can include mirror, anti-reflective, scratch-resistant, and UV. A mirror coating is applied to the front surface of the lens to reflect light, thereby reducing the amount of light actually passing through the lens. Mirror coatings are not transparent, which many prefer. Anti-reflective coatings eliminate lens reflections from the back of the lens, reducing distracting glares that would otherwise interfere with normal vision. Anti-reflective coatings are generally a good idea on any type of lens material, but can be particularly useful on polycarbonate lenses, as they tend to reflect more light. Scratch-resistant coatings protect soft surfaces (such as plastic and polycarbonate) from deep gouges and surface marks. This coating typically increases the lifetime of a set of lenses. Because of their density, glass lenses do not require a scratch-resistant coating.

Does the color of my lens matter? The color of a lens can be as important as the lens material. Grey, yellow, clear and brown are typically the colors that will minimize distortion. Grey lenses are considered neutral because they enhance bright colors. It is also the most popular lens color for everyday use. Yellow and clear lenses are often used for sports related activities, as well as protective sunglasses. Brown lenses can cause some color distortion and have contrast-limiting properties.

What is a photochromic lens? Photochromic lenses, also known as transition lenses, automatically adjust to lighting conditions. They darken with exposure to UV and once the UV is removed the lenses will gradually return to their clear state. You can find photochromic lenses in glass, plastic, and polycarbonate varieties.

What is a polarized lens, and are they worth the extra money? Polarized lenses are well known for reducing glare and improving optical clarity. Polarized sunglass lenses have a special filter within the lens that blocks glare, an especially important feature when used around water and snow. Essentially, polarized shades act like slatted window blinds. When light reflects off a surface, the slatted blinds stop the reflected light from reaching your eye while still letting all the ambient light in. In the end, you'll see more clearly and stave off eye fatigue. So why are they more expensive? The polarization process adds an extra step to the manufacturing process, not to mention the research and development behind a polarized lens. They are more expensive, but your eyes will thank you.

What is lens curvature? Lens curvature refers to the amount of arc in the lens. It is often represented using two numbers, such as 12 x 4.5. The first number (12) would be the horizontal arc (also called the base). A 6 base lens has a more flat, square shape creating a more scholarly look. You will find many 6 base lenses in fashion sunglasses. A larger base like a 9 base is more wrapped and therefore will appear more suited for active endeavors. The second number (4.5) refers to the vertical arc in the lens. 4.5 means it's slightly rounded from top to bottom.

Should I worry about the hinge type? Probably not. Most hinges are made from stainless steel or a water resistant metal alloy to prevent rusting. Many of the hinges found on sunglasses are barrel hinges, which are formed out of interlocking pieces and held together with a single screw. They are inexpensive, durable, and functional. Spring hinges use spring tension to press the temples of the frame closer to the sides of your head. This allows for a closer, more customized fit, but also means they are more expensive.

What is the most popular lens and frame color? The combination of a grey lens in a shiny black frame is the most popular option. We expect this to be our best seller for years to come.

How should I keep my sunglasses clean? They best way to keep your sunglasses clean is to store them in a protective case when not in use. This will also keep your lenses from getting scratched. Because your shades will eventually collect dirt and dust, use a soft cloth and warm soapy water when those spots become unbearable. Many sunglasses come with a micro-fiber bag which is perfect for cleaning on the go.

What should I do if my lenses start peeling or my frames show wear? Sunglasses may start to deteriorate for a couple reasons. It's usually either a manufacturers defect or due to user abuse. Manufacturers warranties do not cover normal wear and tear, but in the event of a defect most manufacturers have exceptional warranty departments. If you have not taken good care of your sunglasses, you may find it difficult to get them replaced but you might get them fixed for a small fee.

Why are some sunglasses so much more expensive than others? The main factors that determine price are lens material, lens coatings, frame material, brand recognition, and construction. Many people believe that purchasing high-end sunglasses simply means paying for a designer name. This is not the case. Inexpensive sunglasses may not give you 100% UV protection. Every manufacturer claims to make the best sunglasses on earth, but for the most part you will get what you pay for. Polarization is more expensive than a non-polarized lens. Titanium frames cost much more than nylon frames. Many customers are loyal to one brand over another and will pay extra for the "cool factor". That's brand power. When you start adding these factors together, it does not take long for a $50 pair of sunglasses to cost $300.

Is it best to purchase sunglasses that are made in Italy? What about China? 20 years ago, we might have told you that any sunglass not made in Italy is either cheap or fake. This is just not the case today. China has delicately refined their manufacturing processes over the last several years and is now producing exceptional sunglasses. Some major sunglass brands have started to transition their entire product lines to China, in an effort to reduce costs and improve efficiency. We suggest you try both to determine what's best for you.

How do I know what sunglasses fit my face? Here are some basic tips. If you have a square face, look for sunglasses that have a slight curve to them. This will help to downplay a strong jaw line. Those with a round face should buy sunglasses that have straight or angular lines. This will accentuate your features. If you have a triangular shaped face, look for something with thin lines that wont sit high on your face. Those with an oblong face tend to look good in most sunglasses, as long as the size of the frames is proportionate with your head. Ultimately, the decision is up to you. If you like them, wear them! Our secret tip: if you love them, buy two more. There is nothing worse than breaking or losing your favorite pair of sunglasses only to find out that they are no longer in production. If you find a pair you cant live without, buy two or three for the future. You'll thank us.

Do my children need to wear sunglasses? Absolutely. In fact, most kids are out in the sun more often than adults and since their eyes are still in the developmental stage, it is extremely important to keep your kids in sunglasses. UV damage happens over time, so the sooner you can protect their eyes, the healthier they will be down the road.

Are sunglasses regulated in any way? Believe it or not, sunglasses are classified as a medical device by the FDA and are the most widely purchased over-the-counter ophthalmic devices that the FDA regulates. As such, any company that manufacturers sunglasses must follow strict regulations. All lenses must be impact resistant and frames must be non-flammable.

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