Lasers commonly used by the aviation community and the military are being recognized increasingly as possible hazards to vision and visually guided tasks. This study investigated the effects of laser-induced visual loss on target acquisition performance. An argon laser was used to produce a temporary central scotoma. Observers searched for variable-contrast aircraft embedded in backgrounds of varying complexity. The laser exposures increased acquisition times 2 to 12 times over baseline levels, revealing that degree of visual deficit was task dependent. Acquisition time increased as background complexity increased and target contrast decreased. However, target motion facilitated acquisition performance and mitigated the laser effect. Although contrast had a systematic effect on acquisition performance, it was clear that factors other than contrast contributed to target visibility. Other factors that may have affected visibility included distractors and masking effects introduced by the structured backgrounds.
Abstract