Choosing The Best Lenses For Sunglasses
The key to getting the best sunglasses is finding the right set of lenses to go with them. The best sunglasses have lenses that fit properly, look great, and help correct any eye conditions you may have - but most importantly, you want them to protect your eyes against harmful UV rays. There are three important factors to consider when choosing the lenses for sunglasses: lens material, lens colour and lens treatment.
The first plastic lenses ever made were constructed from a plastic polymer called CR-39. Polycarbonate lenses were later introduced in the 80's, and to this day, they are the most common material that sunglasses lenses are made of. Polycarbonate lenses are very popular because they are significantly lighter than standard plastic lenses and also more impact resistant, so they are less likely to break if you encounter any knocks and bumps. As a choice of material, polycarbonate lenses are great if you want the best sunglasses for kid or for sporting activities.
If you are getting prescription sunglasses, it’s a good idea to understand the concept of lens index to select what’s best for you. Lens index is a number that describes how efficiently a lens material bends light. In other words, it tells how thick or thin certain lenses would be. Refractive index is the ratio of light’s speed when it travels through air to that when it passes through the lens material. It works inversely, meaning that if a lens index is high, we can infer that light travels more slowly through the lens materials and bends light rays more. Hence, with lesser, thinner and lighter material, these lenses correct the same amount of refractive error as lower index or conventional glass or plastic lenses.
High-index plastic is the latest and greatest type of material used for sunglasses lenses. They are even lighter, thinner and flatter than polycarbonate lenses. In fact, if you have a very powerful prescription then you may find that high-index plastic is the best type of lens glasses' material to choose the best sunglasses lenses. High index lenses are noticeably slimmer, more lightweight and more stylish. Most high index lenses are also aspheric, making them slimmer and eliminating the “bug-eye” look to a great extent.
At Vision Direct, we offer basic lenses starting at an index of 1.5. Thin lenses with 1.61 index are 25% thinner than basic lenses. Even thinner lenses with an index of 1.67 are also available with our Arise Collective Clarity 8K lenses. Then we come to the crowning jewel of thin lenses with an incredible index of 1.74. These are as thin as possible (35% thinner than standard lenses), are ultra strong and effectively correct vision problems with a very pleasing look. All lenses offered at VisionDirect are covered by 20/20 Enhanced Lens Insurance, a warranty based on the value of the frames you purchase with up to 5 years coverage.
Most people believe that darker lenses offer better UV protection, but you may be surprised to discover that the color of the lenses has no relationship to the amount of protection you are getting. This is because the coating which blocks UV rays is actually transparent, meaning that darker lenses for glasses do not necessarily offer the most UV protection. Therefore, lens colour has very little to do with picking out the best sunglasses for you when considering UV protection.
However, the hue of your glasses lenses still plays an important factor regarding visual performance. Some colours are more suited for certain activities, so it is still worth considering which lens colour will be best for your sunglasses.
Generally speaking, darker lenses are a good choice for the best sunglasses if you are looking for lenses that will reduce glare but not distort colour. These glasses lenses will be great if you are likely to be wearing your sunglasses all day. Green lenses for glasses are also good for all day use as they protect your eyes while providing visual clarity that most resembles natural human eyesight. Brown or amber tinted lenses have a red tint which is known to enhance colour contrasts, so they are best suited for sports or activities where accurate depth perception is key, such as tennis, fishing, golf and sailing.
Colour enhancement does not only extend to full tinted lenses. Transition lenses for glasses, also known as photochromic lenses, are also available. The special molecules in these lenses darken when directly exposed to UV light and become transparent when not exposed, which is extremely convenient if you will be moving frequently indoors and outdoors. If you want the best eyeglasses and the best sunglasses without the added price of paying for two pairs, transition lenses might be right for you. We recommend these lenses if you’re at risk when exposed to light and UV rays- example if you have cataract or diabetes, with sensitivity to contrasting light conditions or have recently undergone surgery in your eyes. Children are well suited to photochromic lenses as they spend a lot of time playing outside, are exposed to UV rays for a greater period and their eyes are not fully developed yet.
There is an endless list of lens treatments which you can apply to your lenses, such as anti-scratch, anti-glare, anti-reflective, a UV protective coating, a mirrored coating or even a polarized coating.
However when it comes down to it, if you are investing in the best sunglasses that you want to last for a long time, then it is highly recommended that you should choose lenses for glasses which have at least the first four types of lens treatments.
An anti-scratch coating ensures that your lenses will avoid being scratched and ruined by surfaces like sand, the inner contents of your purse or your shirt sleeve (because you know they always end up being cleaned that way). Anti-glare, anti-reflective and polarized coatings all enhance your visual quality and are great for activities where you will be under intense sunlight (i.e. exposure of more than 10 minutes) and need to reduce glare.
A UV protective coating is essential for protecting your eyes from harmful UV rays, sunglasses lenses should have this coating. Mirrored lenses deflect light, but they are often chosen for aesthetic purposes so it is advisable to choose lenses which also have an anti-glare, anti-reflective and anti-scratch lens treatment applied.
Mirrored coatings have a reflective optical coating on the outer part of the lens. This gives the appearance of wearing small mirrors- which not only looks cool but also has functional benefits. Mirrored sunglasses look very fashionable and reflect more light than regular tinted lenses, making them useful in environments where you may be exposed to a lot of light reflected off surfaces like water and snow. This is why many sports sunglasses feature reflective coatings.
Polarised sunglasses are a great pick for those who find themselves in environments with reflective surfaces such as water and snow. The science behind polarised sunglasses is that the lenses in them are coated with molecules lined up in horizontal rows. They absorb light travelling in a horizontal direction, hence eliminating glare and enhancing colour contrasts. This makes such sunglasses a top choice for athletes and individuals spending a lot of time outdoors who want to receive greater depth perception to enhance their performance.