Basic Experiments for Evaluating Peculiar Ocular Characteristics Caused by Artificial Binocular Vision

Abstract

By using Eye-Sensing Head Mounted Display (ES-HMD), basic laboratory experiments were conducted to evaluate convergent eye movement and pupil size under some specific visual conditions induced by artificial binocular vision; one experimental condition was that asymmetric luminous intensity for both eyes was illuminated. The result shows that each pupil size of both eyes in asymmetric condition is different from in symmetric condition, even if each eye is illuminated by the same luminous intensity for the both conditions. Since the experimental condition would never usually happen in real world, longtime exposure to light in asymmetric luminous condition may lead to visual fatigue. The other experimental condition was binocular vision generated by binocular parallax. It was found that (i) some subjects, who are called vergence normal, can adjust convergence according to the moving target with binocular parallax, but the other called vergence anomaly cannot, and (ii) pupil size in a vergence normal changes with the vergent eye movement induced by binocular parallax. These results show that a vergence anomaly, who is also called stereoanomaly, can be easily detected by using simple test image and observing vergence eye movement or pupil size. The obtained relation between pupil size and binocular parallax is also a new experimental proof of influence of vergent eye movement to the change of pupil size.