Spring has brought us the first bursts of sunshine this year, but with the warmer weather and beach, holiday-like sun rays come hidden dangers.
Sunglasses offer the most effective form of sun protection for our eyes, but there is often a lot of misinformation about them and exactly how they deflect UV rays.
So, let us demystify some of the common myths about UV damage and sunglasses and explain why they are an essential part of personal protection, not just a fashion statement.
Can the sun damage my eyes?
Sunlight is the primary source of UV light. Extended exposure to intense ultraviolet (UV) rays can cause damage to the eyes in a variety of forms. These range from temporary vision loss and macular degeneration to cataracts, photokeratitis (a kind of sunburn of the cornea), and in some cases, complete blindness.
Reflected UV rays often go unaccounted for, but are equally dangerous. For example, fresh snow reflects as much as 80% of UV radiation, seafoam around 25% and dry sand around 15%. Considering that you look downwards more than you look directly up, your eyes are still at risk from these types of rays.
Do all sunglasses block UV rays?
Not all sunglasses are created equal. Many lenses are labelled as ‘sun glasses’ for the purpose of fashion marketing but do not actually offer any protection against UV rays.
There are three types of UV rays: UVB, UVA and UVC.
UVC - the most damaging, but these rays are mostly absorbed by the Earth’s atmosphere before it reaches us.
UVA - rays can pass through the cornea and reach the retina, although very little UVA reaches the retina as the majority is absorbed by other parts of the eye.
UVB - is responsible for a sun tan or sunburn, it can't pass through the glass but can burn your skin and cause eye damage. Conditions such as cataracts, photokeratitis, pterygium (a creamy, fleshy growth on the eye surface) and squamous cell carcinoma (a rare cancerous tumour that occurs on the surface of the eye) are closely linked to these rays.
How do I know if sunglasses offer protection?
Opt for sunglasses that do not transmit any more than 1% UVA and 1% UVB rays. Most glasses will be labelled with the percentage of rays they can deflect, i.e. at least 99% UV protection or 100% UVA and UVB protection.
On some occasions, this can also be written as UV400, meaning it blocks all light rays (both UVA and UVB) with wavelengths up to 400 nanometres
Lenses should be large enough to cover the eye completely, to prevent as much light as possible from passing through the edges of the glasses.
What difference does a lens colour make?
The colour of your lenses affects the level of protection your eyes will receive, and while some colours offer certain benefits, the level of protection they offer will differ.
Pink lenses reduce eye strain, improve the visual depth and offer the greatest amount of contrast. They do not, however, offer the same amount of protection against the light that darker shaded lenses do.
For lower light levels, green lenses offer good contrast, dim glares and even colour perception. As well have to have a unique, aesthetically appealing look, blue lenses also enhance colour perception and define contours.
Yellow lenses offer greater clarity in low-light conditions such as fog and haze, whilst brown and amber lenses contain a red element which helps to improve depth perception.
Grey lenses are incredibly versatile, great for driving and outdoor sports as they reduce brightness and glare.
Brown/ amber lenses have red hues which block blue light, improving depth perception. They are especially great for golf as they increase contrast against blue skies and green landscapes.
From Ray-Ban to Prada, we stock one of the most diverse online selections of designer sunglasses for both men and women.