While protecting your eyes from UVA and UVB light, polarised sunglasses also contains a layer within the lens mixture called a polariser. This layer blocks nearly all reflected glare from shiny horizontal surfaces such wet roads, water and snow slopes. Polarised lenses can cost more than non-polarised sunglasses, but they provide much better visual clarity, free from glare. This sounds good right? But it’d be good to go into more detail to help you decide if they really are worth the extra comfort and clarity and money.
Why is polarised better?
Ok, here comes the science bit… Polarised lenses can block-out glare, but how exactly does this filtration work? Polarised sunglasses will protect your eyes from UV light, but their secondary benefit is that they filter out horizontally orientated light, commonly known as glare. You’ll have experienced this on a bright sunny day walking near large areas of naturally occurring reflective surfaces such as lakes, wet roads or footpaths. Another example is when you are driving on a wet morning and the sun is shining on the wet road surface causing a blinding glare to reflect off the road. Glare happens when sunlight reflects off these shiny surfaces, becoming reoriented and condensed into horizontally aligned light causing you to squint or shield your eyes.
This is exactly why polarised sunglasses are so beneficial because they filter-out this annoying and potentially hazardous glare from passing through your sunglass lens and entering your eye. Non-polarized sunglasses don’t have this function.
Reasons to wear sunglasses
Deciding on polarised sunglasses will largely depend on your lifestyle and frequency of wearing sunglasses: