What is glare?

Annoying and uncomfortable, glare is when natural or artificial light interferes with your vision preventing you seeing properly. This can happen during the day from strong reflections or at night from car headlights.


In the context of sunglasses, this quick article helps explains the effects of glare on your vision and the best way you can minimise it.

Let’s go into a little more detail.


What causes glare?

The sensation of glare is when your eyes cannot cope with the amount of light they’re being exposed to. Very intense light hinders your vision causing discomfort and loss of visual performance.

Sources of glare can vary depending on your environment and the time of day. The most common source of day-glare is from reflective surfaces such as water, cars, buildings and windows.

At night, car headlights are the most dangerous and impactful source of glare.

Year round, reflected sunlight is ever-present. Facing towards the sun, water is one of the biggest culprits of glare.

See the example below.


Daytime example of glare reflecting from waters surface


Do sunglasses block glare?

The only kind of sunglasses that can help to reduce glare are polarised ones. In addition to UV protection, polarised lenses contain a filter which blocks reflected glare for smoother, more consistent vision in varying sunlight. Non polarised sunglasses cannot do this, but still have UV protection.

Square tortoiseshell sunglasses frame with dark grey lenses


Visual comparison of water glare looking through polarised sunglasses and non polarised sunglasses


Types of glare


Distracting glare is especially disliked as it interferes with our focus the most. This is when you’re trying to focus on a task but a strong light source is entering your peripheral vision. For example, when you’re using the computer but sunlight is hindering your line of sight.


Disabling glare or ‘disability glare’ is more serious. This is when sunlight physically inhibits how you see, often described as being ‘dazzled.’ For example, driving towards low level winter sun can seriously diminish your ability to see the road ahead.


For tasks like driving polarised sunglasses can be especially helpful to reduce the effects of reflected glare.

Low level sun, wet roads or nearby reflections from other cars or water put your eyes under tremendous strain whilst behind the wheel of a car.

Over long drives, glare causes visual fatigue which can leave you with that ‘frazzled’ feeling.

If this sounds familiar, investing in high quality polarised sunglasses is a sure bet.

Large black rectangular sunglasses frame


Dual comparison image of road glare looking through polarised and non polarised sunglasses


Does glare cause eye strain?

Yes, glare causes you to squint and strain to see properly. Over long time periods, this causes eye strain and the onset of visual fatigue. The best way to reduce the effects of glare is with polarised sunglasses which diminish these taxing reflections on your eyes.

Regular sunglasses aren’t as effective at blocking glare, therefore won’t reduce the harsh reflections from water or snow.

If you spend a lot of time in the sun, playing sport, fishing or sailing, polarised sunglasses are the best way to prevent eye strain.


Is glare bad for your eyes?

Glare is distracting and often debilitates your vision. The minor effects of glare is visual fatigue when your eyes become tired from straining to see. If unprotected, the major effect of glare is UV exposure which can cause macular degeneration, cataracts and long term skin damage.

Always ensure your sunglasses are rated as UV40 or UV400 which ensures they provide sufficient protection against damaging ultraviolet light.

At Banton Frameworks, all our frames are rated as UV40.


Hopefully you found this article useful.

Thanks for stopping by.


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