Those affected by regular headaches could be suffering from poor binocular vision, the Eye Care Trust has claimed.
Some 12 per cent of people are affected by poor binocular vision, which means that the brain does not correctly process the images that are captured by the eyes.
The trust suggested that more people may realise they have the condition now that 3D films are becoming more popular, as these require the eyes to work in coordination.
"This leads to an inconsistency in viewing the three spatial dimensions (height, width and depth) required to enjoy 3D films in all their glory," the charity explained.
Poor binocular vision can be identified by trained opticians and optometrists, so the trust is urging people to go and get their eyes tested if they feel something is not quite right with their sight.
Research conducted by optometrist Christian Dutton and published on optometry.co.uk revealed that 92 per cent of those working in the optical industry feel that 20 minutes was not long enough to conduct a thorough eye exam.
by Martin Burns