Do I need anti glare on polarised sunglasses?

You don't require anti-glare on the front-surface of polarised lenses as they already block incoming glare via the polariser filter within the lenses. However, anti-reflective may be applied to the rear-surface of polarised lenses to prevent outgoing visible light from reflecting backwards into your eyes.

In other words, polarised sunglasses already provide anti-glare properties. But this works differently to how anti-reflective lens coatings work.

Weird, I know.

To get your head around this, it’s a good idea to understand how they each function, both separately and together. (Yes you can have both at the same time.)

Let's dive in.

 

Person holding up tortoise shell sunglasses

What is anti-glare?

Anti-glare (AG) is a thin chemical coating applied to prescription and non-prescription lenses to reduce reflected visible light from external sources such as water or wet roads. This improves visual clarity by reducing harsh and distracting reflections otherwise known as glare.

This coating sounds very similar to polarised lenses which also block glare. But they aren't the same as explained further below.

 

 

What are polarised lenses?

Polarised lenses use a filter called a polariser which is either applied externally to the lens or internally sandwiched between the outer and inner lens layers. This filter is a very thin film, which hosts microscopic rows of vertically aligned molecules which only transmits vertically orientated light through the lens.

When visible light reflects off flat surfaces such as the sea, it becomes horizontally orientated and blindingly strong to look towards (glare). Polarised lenses block this glare which provides a much smoother visual experience, reducing the strain put upon your eyes.

This is why polarised lenses don't require an anti-glare coating, as the lenses already contain a filter which eliminates glare (and more effectively too!)

But, there is a helpful coating which can be applied to polarised lenses that's commonly confused with anti-glare.

 

 

What is anti-reflective?

Anti-reflective (AR) is another type of chemical coating which can be applied to the rear surface of sunglasses lenses. This increases the amount of visible light which passes through the lens, instead of being reflected backwards into your eyes; also known as 'bounce back'.

'Bounce back' is a common occurrence with fashion orientated sunglasses as they typically have low base curvatures (flat frame fronts) which create gaps between your face and frame. This tends to allow sunlight to get behind your lenses, either from above or from the sides which can be annoyingly reflected back into your eyes.

Rear-surface anti-reflective coating prevents bounce back.

It lets the visible light outwards from the inside of your frame, whilst the polarisers block glare from the front. Together, they make your vision ultra smooth, free from glare or any annoying internal reflections.

 

 

Young male walking beside beach wearing stripey blue shirt and tortoise sunglasses

Should I get anti reflective coating on polarised sunglasses?

Recreational (non-sporting) sunglasses tend to have flat frame curvatures which allows visible light to get-in behind your lenses and reflect backwards into your eyes. Anti-reflective coatings prevent this from happening, therefore are a good method of improving the performance of your sunglasses.

If your current sunglasses lenses don’t feature a rear-surface anti-reflective coating, you may experience annoying reflections depending on the angle between you and the sun. Sometimes, you even see your own eyes which is just annoying and also kinda creepy.

If sports sunglasses aren't your thing, polarised lenses with an anti-reflective coating are an exceptional combination to aid external glare and internal lens reflections.

 

Benefits of anti-reflective coating on polarised sunglasses

  • Polarised lenses block external glare
  • Glare is harsh reflections from flat surfaces such as water
  • Rear-surface anti-reflective prevents internal lens reflections
  • Polarised lenses reduce eye strain from external visible light
  • Rear-surface anti-reflective reduces eye strain from internal visible light

 

 

Tortoise and grey sunglasses frames sitting together on top of white rock on beach

Are polarised lenses better?

Polarised lenses are better for improving visual comfort, but they're no more UV protective than CE marked or UV400 rated sunglasses. In addition to primary UV protection, polarised lenses have the secondary benefit of blocking glare from water or wet roads which is why they're often deemed as a better type of lenses.

 

Benefits of polarised lenses

  • Polarised lenses contain an inbuilt chemical layer called a polariser. This is what informs the polarised sunglasses meaning.
  • This chemical layer is able to block horizontally orientated sunlight (glare) which is reflected from large flat surfaces such as water, ice, snow or shiny ground surfaces. This how polarised sunglasses are already anti-glare because of their in-built polariser.
  • Polarised lenses diminish horizontal light which is why they’re so effective at reducing eye strain. Less glare means less squinting which also reduces the likelihood of headaches.
  • Polarised lenses are particularly popular with sportspeople who spend long periods near water or snow.
  • Polarised lenses are still fully UV protective as the polariser-layer only blocks glare and provides no additional ultraviolet protection.

 

 

Young man on beach facing viewer whilst adjusting his sunglasses with both hands

          Which sunglasses are better polarised or non-polarised?

          Both these types of sunglasses should and must block ultraviolet (UV) light. However, polarised sunglasses have the secondary benefit of blocking reflected glare from surfaces such as water or wet roads. Non-polarised lenses can't do this, therefore can be viewed as an inferior.

          However, polarised or not, your sunglasses need to block at least 99% of UV light in compliance with European standards; EN 1836:2005.

          Just because lenses are polarised, doesn’t mean they’re any more or less capable of blocking the damaging frequencies of ultraviolet light.

          As a rule of thumb, always check the UV rating of any sunglasses. At the very least, the frame should bear the CE mark or even better, UV400.

          CE means the lenses block 99% of ultraviolet light ranging up to 380nm.

          UV400 means the lenses block 99% of ultraviolet light ranging up to 400nm.

          If you'd like to know more about the UV protection of polarised sunglasses, check out this helpful blog post.

           

           

          Young man standing at the beach wearing sunglasses with the sea behind him

          FAQ's

          Do I need anti glare on polarised sunglasses?

          No. You don't need anti-glare on polarised sunglasses. They already block glare from their in-built polariser which is sandwiched within the layers of each polarised lens. However, anti-reflective may be applied to the rear surface of the lenses to prevent light from bouncing back into your eyes.

           

          Are polarised better?

          In some cases, yes. For tasks which require long periods of visual focus, such as driving, outdoor reading or sports, polarised sunglasses are a better choice of sunglasses lens. Over time, they reduce the strain placed on your eyes from reflected glare and prevent you from naturally compensating by squinting to see.

           

          Do sunglasses need to be polarised?

          No. Sunglasses don't need to be polarised as they only improve visual comfort. Regular, non-polarised sunglasses which are CE marked or UV400 rated are perfectly good for protection against invisible ultraviolet light.

           

          Hopefully you found this article helpful. If so, please check out our other polarised sunglasses blog posts for more insights.

          Thanks for stopping by.

           

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