Excessive screen gazing may cause digital eye strain

Too much time staring at a screen during lockdown can cause digital eye strain previously known as computer vision syndrome, says UKZN lecturer in the Discipline of Optometry, Dr Alvin Munsamy.

"If you consider that a computer is not the only electronic device we use today then digital eye strain is a better description as it encompasses all electronic devices with LED displays."

Munsamy said the condition could cause blurred distance/near vision, difficulty changing focus, eye fatigue, general discomfort and redness of the eyes. Neck and shoulder pain were other symptoms.

He suggests use of the 20:20:20 rule to avoid the condition - every 20 minutes, look away about 20 feet (6m) for 20 seconds. The ideal distance between the eyes and the screen is between 50cm and 70cm.

"Remember to blink every four seconds and ensure you are using spectacles prescribed by your optometrist. Consider wearing spectacles with blue blocking coatings and/or anti-reflection coatings and use artificial tear supplements which can be obtained over the counter at a pharmacy.

"Your screen should be at eye level with gaze slightly depressed around 15-20 degrees," said Munsamy.

"Ensure your children don't work too close to screens or for long periods of time to prevent myopia progression. Make sure they have time to play and switch off devices being used one to two hours before bedtime to ensure sleep onset and quality are not affected."

He said continuous screen use causes eye strain so it is important to take regular breaks. "In the case of mobile phones, be cautious as they have smaller font sizes and are used at a closer working distance. Screen time reduces blink rate and also causes poor blink quality, resulting in evaporative dry eye."

Light from LED screens emitted high energy visible blue light similar to the sunlight, except not as strong, and this was also thought to cause digital eye strain. The light in a working environment can cause discomfort glare.

"Do not spend long, continuous periods at the screen of an electronic device. We must use these devices as part of our new norm, so maintaining proper visual hygiene will ensure a healthy 'relationship' with them," he added.