Study suggests three-dimensional vision may be possible with one eye

Science News : It has been known since the 1830s that under the right circumstances people will see a flat image as three-dimensional if it’s presented to the viewer as two separate images—one for the left eye and one for the right eye. The viewer’s brain merges the two images into one. A new study suggests that it may be possible to perceive a flat image as 3D by looking through a small hole with just one eye. Dhanraj Vishwanath and Paul Hibbard of the University of St. Andrews in the UK had test subjects view flat images through a pea-sized hole. As long as they couldn’t see the edges of the image, the majority of the viewers reported seeing it as 3D. Vishwanath thinks that, when the brain doesn’t have evidence that the picture is flat, it may attempt to view the objects in the picture the same way it views actual objects. However, some scientists have objected that the study relies on subjective findings and requires quantitative evaluation. Vishwanath argues that the effect itself is qualitative and cannot be evaluated quantitatively. He and his team are now evaluating the effect on subjects who suffer from strabismus, a misalignment of the eyes that prevents binocular 3D vision.