What are polarised lenses?

Polarised lenses contain a filter called a polariser which diminishes reflected glare from reflective surfaces such as water, snow, buildings or cars. This reduces eye-fatigue, giving you smoother, more consistent vision in varying sunlight.

 

When sunlight bounces off the ground, water or snow, it becomes incredibly harsh to see properly, even with regular sun lenses on.

Polarised lenses have an advantage compared to regular lenses as they block reflected sunlight to improve your visual comfort and optical clarity.

During prolonged sun exposure, polarised lenses prevent you from squinting and straining to see. This is why they’re considered a superior lens-type making them popular for long-term visual tasks such as driving and outdoor sports.

Polarised lenses are just as UV protective as non-polarised equivalents.

 

 

 

Are Polarised lenses worth it?

Despite their extra cost, polarised lenses are worth it if you spend long durations in the sun and require extended visual focus.

On average, they’re 30% more costly than non-polarised versions but have the benefits of glare reduction which takes the strain off your eyes over long periods outside.

For driving or sport, the accumulative effects of eye-fatigue are lessened by polarised lenses.

 

 

 

Bright sunny sky with strong sunlight and sparse white clouds

 

Are polarised sunglasses better?

Polarised sunglasses are equally UV protective as non-polarised equivalents.

However, they provide clearer, more consistent vision in varying sunlight with reduced strain on your eyes from reflected glare.

Glare reduction is a secondary benefit to UV protection but this bonus improves the performance of your sunglasses.

 

 

 

Illustration showing how polarised sunglasses reduce horizontally polarised light

 

What is meant by polarised sunglasses?

Within their layered structure, polarised sunglasses contain a filter called a polariser. This filter uses vertically aligned molecules to diminish horizontally orientated sunlight (glare.)

Glare is what strains your eyes and interferes with your perception through your sunglasses.

 

 

 

Close side view of man wearing tortoise polarised sunglasses

 

How can I tell if my lenses are polarised?

At arm’s length, look through one of the sun lenses in its usual orientation. The, slowly rotate the sunglasses frame whilst still looking through the same lens. If it goes noticeably darker, the lenses are polarised.

This happens because of the orientation of the polariser within the lenses. As you change the lens-angle to beyond 45° it blocks much more light.

Another method is to overlap two sunglasses frames at opposing angles. One horizontal and one vertical. If the lenses are polarised, they will block nearly all visible light.

 

 

White yacht sailing on the sea on bright sunny day

 

How can you tell if sunglasses are UV protected?

Sunglasses sold in the UK and EU must be rated and stated as UV40 or UV400.

This rating means the lenses can block 99-100% of UVA and UVB light to 400 nano-metres in compliance to European standard: EN 1836:2005.

UVA and UVB are the most damaging frequencies in the ultraviolet spectrum.

Banton Frameworks sun lenses are all UV400 rated.

 

 

 

Close view of man in red car wearing brown tinted sunglasses and blue shirt

 

What colour lens is best for sunglasses?

The most versatile tint colours for recreational sunglasses are grey, brown or green. Generally, these are the best for varying light conditions and help to reduce glare.

In addition to tint colour, the darkness of sunglasses can aid their performance and your overall visual experience.

For help with sunglasses darkness, check out this handy article.

 

Side view of bearded man on sail yacht wearing polarised sungasses and white shirt

 

Are polarised sunglasses darker?

Polarised sunglasses can be marginally darker because their lenses block-out horizontal light. Non-polarised equivalents don’t do this, therefore can seem lighter depending on their tint darkness.

The darkness of sun lenses is determined by its visible light absorption percentage (ABS%.) Recreational sun lenses can vary between 20 to 80 ABS%.

Learn more

 

Three quarter view of bearded man on sail yacht wearing polarised sunglasses and white shirt

 

Polarised sunglasses disadvantages

Polarised lenses aren’t always the best option.

As listed below, there are drawbacks to the way these lenses work.

 

They darken LCD screens

On devices such as your phone, digital car dashboards and petrol pumps, their screens emit pre-polarised light. Normally, this helps you read them in varying light conditions. But polarised sunglasses can interfere with this and blacken them completley.

 

Not good for snow sports

Polarised lenses can make it difficult to see differing colours of white. Because they block glare, shiny patches of ice become ‘flattened’ and hidden to skiers or snowboarders putting them at risk of an accident. For this reason, non-polarised lenses are preferred to spot this kind of hazard.

 

Avoid cheap versions

Low-cost polarised lenses are often coated with a polariser film which can peel or deteriorate over time making the lenses ineffective at blocking glare. Good quality polarised lenses are made in a layered structure with the polariser built-in. This improves quality and longevity.

 

Bearded man facing viewer standing on white yacht wearing sunglasses and white tshirt on bright sunny day

 

Summary

Polarised lenses have the secondary benefit of glare reduction which helps minimise visual fatigue over long periods of focus.

On average, they cost 30% more than non-polarised lenses and provide the same amount of UV protection.

The most common tint-colours for polarised lenses are grey, brown and green which cater for recreational scenarios such as driving.

Hopefully you found this article useful.

Thanks for stopping by.

 

 

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