Changes in ocular factors according to motion-in-depth of 3D display and viewer age

Purpose To compare changes in ocular factors according to the motion-in-depth of three-dimensional(3D) images and viewer age after watching a 3D display. Methods 30 healthy subjects were enrolled(17 in their 20-30s, 13 in their 40-50s). Subjects watched a 3D display with a 1° and 3° binocular disparity with two defined velocities(slow, 105mm/s; fast, 257mm/s)for 30 min. The near point of accommodation(NPA) and convergence(NPC), and tear break-up time(tBUT) were measured before and after watching the display. All measures were remeasured until it returned to the baseline. Questionnaires on subjective symptoms were collected before and after watching the display. Results NPA increased more in the fast motion-in-depth than slow motion-in-depth after watching 3D video. NPC increased more in the fast motion-in-depth than slow motion-in-depth after watching 3D video with 3° disparity only. According to the age, NPA increased more in the 40-50s group than in the 20-30s group after watching with 3° disparity/fast motion-in-depth only. NPC increased more in the 40-50s group than in the 20-30s group after watching with 3° disparity/fast motion-in-depth and slow motion-in-depth. The recovery time of NPA and NPC were same results as the change of NPA and NPC. However, the changes of tBUT were not significantly different between the two age groups and between the two motion-in-depths. Changes of subjective symptoms were different according to the motion-in-depth of 3D display and viewer age. Conclusion We quantitiatively investigate the effect of motion-in-depth of 3D display and viewers’ age on the viewers’ visual function. The results indicate that motion-in-depth might be considered in determining visual comfort of 3D display, especially in older people.