Questions from our patients about ‘blue light’ are becoming more frequent, in part due to new products promising to block or reduce damaging blue light, and because of increasing use of screens and light sources meaning that we are exposed to more blue light than in the past when we were not all attached to our digital devices and lightbulbs were usually tungsten yellow. So – are these ‘blue blocking’ products necessary?
Firstly, what is ‘blue light’? Natural and artificial light is made up of many wavelengths of visible colour. Blue light falls at the end of this spectrum, from 400-525nm.
Does blue light damage the eye? In animal studies research has found an association between blue light or visible light and retinal damage. However, studies on humans can only estimate blue light damage, as in the normal course of daily life eyes are exposed to light across the spectrum.
Is blue light an increasing threat? Our use of lighting is changing dramatically: over the last 10 years we have seen an increase in use of LED (light emitting diode) and fluorescent lighting, as well as white light LEDs in the backlit displays of tablets, smartphones and computers. These light sources are relatively higher sources of blue light than traditional incandescent light bulbs. Despite that, they emit many thousands of times less blue light than natural daylight. Even though these devices are well within international safety limits, research has suggested that excessive exposure to visible blue light can cause eye strain and eye fatigue. It may also augment sleep dysfunction.
Are there health benefits from blue light filtering lenses? There may be clinical situations where a blue light filtering IOL is recommended to prevent or slow the progression of age-related macular degeneration, but currently there is insufficient evidence to support this.
Is there evidence to use blue light filters on spectacle lenses? In some cases blue light filters may reduce eye fatigue, enhance sleep, or preserve macular function but as there is limited scientific evidence, we cannot guarantee beneficial results. However, patients with these issues may request these lenses to see if they help them, and of course they will be able to see just as clearly with these lenses as with unfiltered lenses.
What Blue Light filtering products do Donner Optometrists use?
BlueControl from Hoya is a coating that has been developed to make vision more comfortable from over exposure to blue light emitted from digital devices. It can be applied to most spectacle lenses including single vision, varifocal and even bifocals. BlueControl neutralises blue light and also has other benefits: it is scratch resistant, water, grease, and dirt repellent. The coating also provides higher contrast, improved clarity and colour perception to optimise your vision.
If you have any questions then please contact Donner Optometrists a on 01372 458318 and our dispensing opticians will be happy to give you further information.