SYDNEY CITY 
Shop 6, 60-70 Elizabeth St
Sydney NSW 2000
T: 02 9223 6566
WAHROONGA VILLAGE
Shop 3, 2 Redleaf Ave
Wahroonga NSW 2076
 T: 02 9487 3551

The Eye Piece, 2019

Blue Blocking Lenses: A Beginner's Guide

Something new you may have heard about the last time you went shopping for glasses is the phrase "blue blocking." At present, there is a lot of misinformation regarding this technology, so we decided to put together a no-nonsense guide to help you decide if it is right for you.

Theory Behind Blue Light

When it comes to light, the shorter the wavelength is, the more dangerous. Of all the visible colours, blue light has one of the shortest wavelengths. A short wavelength means that light can easily get to the back of the eye and potentially cause damage. There is an invisible short-wavelength light that gets a lot of bad press in Australians: ultraviolet (UV) light. The damage that overexposure to UV light can cause is common knowledge, and since it is invisible, it is hard to tell how much exposure we are getting. We do not think that blue light is nearly as dangerous as UV light, since it has a longer wavelength and therefore less energy. But with our noses in our iPhones, we are exposed to blue light at higher levels than ever seen before. This leaves us to wonder if we should be protecting ourselves from blue light.

Appearance

Many of our patients are concerned with the appearance of a blue blocking lens. More outdated blue blocking lenses have a yellow tint, but the Blue Control lenses available at The Eye Piece do not. Rather, they have a blue bloom. A lens' bloom is the colour that is reflected off of the lens coating when light hits it. For example, a standard anti-reflective coating will have a green/purple bloom.

See if you can spot the difference above; the pair of glasses on the left are HOYA Diamond Finish anti-reflective lenses, while the pair on the right are HOYA BlueControl lenses. This can be tricky to see, even to the trained eye, but the difference is negligible nonetheless. Feel free to ask to see a sample in store to further investigate.

 

Sleep & Fatigue

As you might expect, the light we are exposed to helps regulate our sleeping patterns. If we manipulate how much light exposure we get, we can theoretically mess with our body clock.

When the sun sets in the evening, our bodies respond by releasing melatonin, which makes us feel calm. When the sun rises, the morning light stops the secretion of melatonin to wake us up. Generally speaking, the brightest, highest-energy light – blue light – is the light that will then keep you most awake and alert. This makes sense, since the brightest part of our day is the time which we are usually working hard and should be staying awake.

In our modern age we are bombarded with artificial blue light from countless sources. In this way, our melatonin systems can get confused, often keeping us awake at odd hours leading to eye strain and abnormal sleeping patterns. Research suggests that by blocking blue light, our melatonin systems can be more naturally regulated, rather than being artificially managed by our screen time. For those of us racking up the hours in front of a screen, Blue Control could offer our bodies a helping hand in this modern age and may even be the first step to a better night's rest and less daytime sleepiness.

Eye Damage

It is easy to be swept up in unfamiliar scientific jargon, especially when your health is on the line. Here, we have summarised where we think the research is at in making a decision about blue light.

Some researchers suggest that overexposing the eye to blue light could perpetuate eye deterioration, including macular degeneration. As it stands, most eye health professionals agree that the link between macular degeneration and blue light exposure does not yet hold enough evidence to be confidently recommended as a preventative measure. As a result, there is no consensus within the scientific community as to whether or not blue blocking technology should be recommended in this way. It might be just as effective to wear a tin-foil hat to prevent macular degeneration.

At The Eye Piece, we are committed to delivering our patients with the most accurate information we can get our hands on. As optometry evolves and improves, so will we; and we are excited to be part of such a dynamic industry. If you have any questions or comments, we would enjoy the engagement.