Quick Answer: Digital eye strain, also called computer vision syndrome, is a group of eye and vision symptoms caused by long periods of screen use. It is usually temporary and eased by better screen habits, but persistent symptoms deserve an eye examination.

What are the symptoms?

• Tired, burning or dry eyes
• Blurred vision, or difficulty refocusing between near and far
• Headaches and aching around the eyes, neck or shoulders
• Increased sensitivity to light

What causes it?

We blink much less while looking at screens, so the tear film dries out. Close focusing for hours, glare, poor lighting and a badly positioned screen add to the strain.

How can it be prevented?

• Follow the 20-20-20 rule: every 20 minutes, look at something 20 feet away for 20 seconds
• Blink consciously and use lubricating drops if advised
• Position the screen slightly below eye level, at arm's length, and reduce glare
• Keep your glasses prescription up to date

Read more in our guides on preventing digital eye strain and computer vision syndrome.