Polarised Sunglasses – Optometrist Hurstville
What are polarised sunglasses?
When visiting our Eyes and Specs Optometrist store in Hurstville, our shop assistant may ask if you want polarised sunglasses or sunglasses with a polarised lens. However, you may be wondering, what are polarised sunglasses? Before answering this we need to understand the concept of ‘glare’. Light travels in waves and is often scattered in different directions as it bounces off an object’s surface. Our eyes interpret and perceive this incoming light to form a vision of the object and its surroundings. However when this light bounces off a horizontal surface that is highly reflective such as the water at a beach or snow on a ski field then the light vibrates in one direction horizontally. This concentrates the light hitting the eye directly. This concentrated light is known as ‘glare’.
Polarised sunglasses main objective is to prevent or reduce light glare from hitting the eye. This is done by treating the lenses with a chemical filter that filters out the glare. The filter is applied vertically so that only vertical light can pass through to the eyes. As glare is usually horizontal light, any horizontal light will not pass through to the eyes which helps reduce or eliminate glare from hitting the eyes directly.
What are the advantages of polarised sunglasses?
The advantages of polarised sunglasses are:
- Reduced glare and reflection – By reducing glare from directly hitting your eyes you will give greater visibility and awareness of your surroundings. This will help you avoid obstacles that could cause injury or accident.
- Clear vision with greater clarity – Filtering out glare will allow you to improve your view to a greater precision as your eyes are not distracted by blinding light.
- Reduced eye strain – Glare can create immense strain on your eyes. This is because your eyes need to work harder to process the light coming in to decipher the actual objects apart from the glare. You can see this often when people are squinting their eyes or turning away to avoid glare. This leads to tired or sore eyes, which can be minimised through the use of polarised sunglasses.
What are the disadvantages of polarised sunglasses?
The disadvantages of polarised sunglasses are:
- Difficult to see LCD screens – LCD screens emit polarised light, and subsequently polarised sunglasses filter out this light making them difficult to see. This is often the case for car LCD displays, such as your heads-up display that may show the speed at which you are travelling or GPS directions. In this instance, and for safety reasons, avoid using polarised sunglasses when looking at LCD screens.
- Not suitable for low-light situations – The polarised chemical coating typically darkens the lens which makes it harder to see in low-light situations such as night-time driving.
- Cannot be used on regular reading glasses – As the lens is darker they cannot be used for regular reading glasses as they will make it more challenging for the eyes to visibly read characters.
Who should wear sunglasses?
Polarised sunglasses should be used by anyone that is typically around high-glare environments. Examples of this include outdoor sports enthusiasts that require glare reduction to have greater clarity (e.g. beach volleyball, golf, long-distance running), workers close to water (e.g. lifeguards, fishermen), or those typically in a high-glare environment (e.g. on the snow field or large water areas).
Polarised versus UV Protection?
An important misconception to be aware of is that polarised sunglasses provide UV protection. This is not the case. Polarised sunglasses are primarily to reduce glare, whereas UV protective sunglasses are there to reduce your eyes’ exposure to the harmful UV rays from the sun. UV exposure can lead to temporary blindness, photokeratitis, cataracts, and eye damage. So if you are looking for polarised sunglasses and UV protection, make sure you read the label on the glasses to ensure they offer both polarised and UV protection.
How to tell if your sunglasses are polarised?
The assistant at the optometrist or sunglasses stores will be able to advise if your sunglasses are polarised. However other ways to tell are by viewing the sunglasses in glaring light to see if they reduce the glare and make it easier to see. Alternatively, you can also view them while looking at an LCD screen. If the sunglasses are polarised they will filter the content being displayed on the LCD screen as LCD screens already emit polarised light.
Alternatives to polarised sunglasses?
If you cannot get access to polarised sunglasses or they are uncomfortable, some alternatives to consider are:
- Mirrored sunglasses – Mirrored sunglasses decrease the light entering your eyes by reflecting the light of the mirrored lens.
- Photochromic lenses – Photochromic lenses will naturally darken when exposed to a certain amount of light, subsequently assisting in reducing glare.
- Anti-reflective coating – Some sunglasses and reading glasses have an anti-reflective coating which also helps reduce glare.
Visit the Eyes and Specs Optometrist store in Hurstville
Contact us or visit our Eyes and Specs Optometrist Hurstville store to browse our wide range of polarised sunglasses including Ray Ban, Oakley, Prada, Gucci, and more.