Safety drive screens out the blue light

For those who have cannot help but stay glued to screens, Gualino prescribes special glasses to filter out the blue light. Photo / Getty Images

Makers react to health warning on harmful effect of rays from our electronic devices.

As it gets harder to tear our eyes away from smartphones, TV sets, tablets and computers, concerns are growing over a blue light emitted by their screens, blamed for harming the retina and causing interrupted sleep.

Electronics giants are turning crisis to an opportunity, quickly declaring that their latest products have "safe" screens.

At the IFA mega consumer electronics show in Berlin, Dutch company Philips is showcasing a new computer screen technology called "SoftBlue", which it claims is gentler on the retina.

"We are shifting the harmful blue light frequencies, which are below 450 nanometres, to above 460 nanometres," said Philips' marketing director Stefan Sommer.

Other brands have also seized on "safe" screens as a new selling point.

"We've been told from a very early age by parents that too much screen time in front of a TV or a computer is bad. So a 'safe' screen might resonate with consumers," said Paul Gray, an analyst at IHS Global Insight.

Because they generate a high intensity of light from just a low amount of energy, light-emitting diodes (LEDs) are used to light smartphones, televisions and computers.

But the blue ray emitted at the same time is thought to pose potentially serious health consequences.

Is it all scare-mongering or scientific fact? Serge Picaud, a researcher at the Institute of Sight in Paris, has a more measured take on it.

"We should not be so afraid that we bin all our screens," he said.

Picaud carried out a study in 2013 in which he exposed sample retina cells from a pig - similar to those found in humans - to different wavelengths of light, and found those between 415 and 455 nanometres killed the cells.

In other words, deep blue light, which is close to ultraviolet light, is particularly harmful to eyes.

However, said Picaud, "that must be taken in proportion, as the light intensities produced by our screens are still relatively weak compared to sunlight".

French ophthalmologist Vincent Gualino also believes that "we should not be afraid of the screens".

"The real problem is over-consumption," the specialist on retina illnesses said, warning people against spending more than six hours in front of their screens.

Children's eyes were most vulnerable, as their retinas are clear and they "will be exposed over 40 or 50 years".

For those who have cannot help but stay glued to screens, Gualino prescribes special glasses to filter out the blue light.

Such glasses are widely available in Japan, and in France, lens maker Essilor sells lenses that screen out the harmful rays.

- AAP