Visual fatigue induced by optical misalignment in binocular devices: Application to night vision binocular devices

Abstract

The additional and perhaps unnatural eye-movements required to fuse misaligned binocular images can lead to visual fatigue and decreased task performance. The eyes have some tolerance to optical misalignment. However, a survey of the scientific literature reveals a wide range of recommended tolerances but offers little supporting experimental evidence. Most experimental studies are based on small numbers of participants exposed to brief periods of optical misalignment. Therefore, these published tolerance limits might have limited relevance for long-duration exposure to misaligned binocular devices. Prolonged use of binocular devices may cause visual fatigue irrespective of binocular alignme..