Delays in Laser Glare Onset Differentially Affect Target-Location Performance in a Visual Search Task.

摘要

The present study examined the effects of low-intensity argon-laser glare on the visual search performance of aviators. Using a modified backward-masking paradigm, subjects were exposed to laser glare, either while seated in a cockpit simulation trainer with attached F-15 windscreen assembly. Brief exposure to laser glare, either 25 or 50 ms after a visual scene's onset, produced significant decrements in target-detection performance relative to a no-glare control whereas a 300-ms delay of laser glare onset had very little effect. The intensity of the light entering the eye (.38 uW/sq cm) and producing these effects was far below the Maximum Permissible Exposure (MPE) limit for safe viewing of coherent light. In addition, these effects were modulated by a target's distance from the center of the beam path (also center of the visual display). Specifically, targets closest to the center of the beam path were responded to the most slowly and with the least accuracy. This study demonstrated that the presence of the laser glare is not sufficient, in and of itself, to diminish target-detection performance. The time at which laser glare is experienced is an important factor in determining the probability and extent of visually mediated performance decrements.