Ultraviolet Radiation (UVR)
Evolution, like other good quality sunglasses, eliminate solar ultraviolet radiation (UVR), in particular the more damaging UVB radiation. UV rays from sunlight can damage the retina and the lens of the eye. Too much exposure is linked to conditions like cancer of the eyelids, cataracts and age-related macular degeneration. Sunglasses that provide maximum UVR protection are CE marked and UV400 rated: all Evolution sunglasses and eyewear meet this requirement. They will, therefore, provide the eye with substantial protection against solar UVR and reducing the amount of UVR that the eye is exposed to over a person’s lifetime is highly beneficial.
Polarised (Polarized) Sunglasses
Polarised (polarized) lenses are different to standard sunglass lenses; they have a special film either sandwiched between two other layers of the lens or applied to the front of a lens. What this special film does is eliminate the glare reflecting off a surface like a pavement, road, water or snow. Lightwaves from the sun travel in all directions but when sunlight strikes a surface, it becomes polarised (concentrated) resulting in glare; a polarised lens will eliminate this harsh glare. The result is the ability to see light in its pure state. Objects will appear more defined, sharper and naturally coloured. Instead of squinting to minimise glare, a polarised lens will allow your eyes to see colours with true clarity. Because polarised lenses block glare reflected off a surface (road, pavement, water or snow) they are popular with sailing, boating and watersports enthusiasts, fishing enthusiasts, snow sports enthusiasts, runners, cyclists and drivers. When used for fishing a polarised lens means you will be able to see down below the surface of the water.
Although polarised lenses provide lots of vision benefits it is important to note that the majority of polarised lenses (including Evolution polarised lenses) are made from a material called TAC which is relatively thin and does not provide impact protection. For sports such as shooting where impact protection is important a polycarbonate lens is required.
Lenses colours and their uses
- Grey – The most popular lens colour it reduces all light equally and does not increase contrast – best for bright light and sunny conditions.
- Smoke – Similar to grey but usually has a blue or brown ‘hue’. It is used as the base colour when a mirror finish is applied to the lens.
- Green / G15 – First popularised by Ray-Ban with their classic aviator sunglasses. Creates a soothing tone and adds contrast; a good alternative to plain grey for bright sun conditions.
- Amber / Brown / Vermilion – Popular colours that give a warm appearance and they increase contrast (objects will appear in sharper focus), suitable for most weather / light conditions.
- Yellow – A light enhancing, high contrast colour ; good for poor light, low visibility, dull or cloudy conditions.
- Clear – For protecting eyes from impact, dust / dirt or abrasion.
- Red / Rose / Orange – High definition lenses that filter out blue light which is known to cause eye strain and fatigue. Objects appear sharper and more clearly defined; good in overcast conditions.
- Purple – A great all-round colour that gives a “soothing” appearance. It has also become widely adopted by clay target shooters; known as ‘the background neutraliser’ it dulls a green / brown background and enables the shooter to more clearly see any clay target colour against a dark background. Purple is also becoming a popular colour for golfers.
- Blue – A blue lens can highlight the colour yellow and gold so it can be beneficial to tennis players (yellow ball) and archers (gold bull).
- Mirror lenses – Flash and full mirror are coatings applied to the front of the lens (usually applied to a base ‘smoke’ lens). The ‘Revo’ mirror is where more than one mirror colour is used. They are primarily for cosmetic effect but also increase the filtering power by reducing the amount of light interference.
The Category number equates to a percentage of the VLT (Visible Light Transmission); how much light the lens lets through, as follows:
Category 0: 80-100% VLT
Category 1: 46-79% VLT
Category 2: 18-45% VLT
Category 3: 8-17% VLT
Category 4: 3-8% VLT
The following is a general guide to the Categories that apply to different lens colours:
Category 0 – Clear, Light Yellow, Pale Orange and Yellow
Category 1 – Orange, Rose & Vermilion
Category 2 – Purple, Red, Amber & Light Brown
Category 3 – ‘Standard’ Grey & Brown
Category 4 – Dark Grey & Dark Brown
Multi Lens Interchangeable Eyewear Sets
These have become very popular because they give a choice of lenses fitting the same frame. They will typically come with at least 3 different lenses such as grey, yellow and orange. It means you can change the lens colour to suit the light and background conditions. Evolution has one of the largest ranges of multi-lens sets of any manufacturer.
Polycarbonate is the lens material favoured by sports eyewear brands like Evolution because it’s very light but shatterproof and impact resistant; providing a very high degree of eye protection: 20 times the impact strength of glass and up to 10 times the impact strength of normal plastic. However, polycarbonate is prone to scratches so it’s important to take care of the lenses and always keep your sunglasses or eyewear in a case or carry pouch when not in use: all Evolution models are supplied with a soft carry pouch and many with a hard case too.