Abstract
Purpose :
Military pilots are required to attend to multiple items displayed within night vision devices. These displays may be biocular, thereby placing demands upon pilots’ binocular vision. We sought to examine if misalignment of binocular night vision systems reduced the attention given to peripheral items (gauges) in the display.
Methods :
Five participants undertook a 30-minute simulated helicopter tail chase whilst simultaneously monitoring gauges at ±12 degrees horizontally and vertically from centre of the display. Participants were tested in aligned and misaligned conditions. Misalignment of 30 arcmin divergence and 30 arcmin dipvergence was presented to all participants. One participant underwent further trials with 45 arcmin of misalignment. Gaze was recorded at 1kHz with an Eyelink 1000 Plus eyetracker.
Results :
Time spent examining gauges was significantly different between individuals. In the misaligned condition time spent fixating the gauges was either similar to or less than the time in the aligned condition for all participants. Change in dwell time ranged from +10.8% to -18.7% (mean -6.7%) for the 30 arcmin misalignment condition. Only one participant had an increase in dwell time. This participant was trialled with the higher misalignment which produced a decrease in time spent on the gauges (-12.2%).
Conclusions :
Increasing misalignment of night vision devices results in a reduction of time spent viewing information displayed in the near periphery. The amount of effect varies in individuals. This may result in delayed or missed perception of important information.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.