Human Visual Limitations on Suprathreshold Contrast Perception through ANVIS.

摘要

Recent success on the battlefield underscored the tactical advantage of night operations and image intensifying devices. It is important to understand both the benefits and limitations inherent in these devices. While several studies have focused on spatial resolution thresholds through image intensifiers, less is known about visual perception at suprathreshold levels of stimulation. Such information is necessary to anticipate and predict visual performance under various conditions. In this study contrast matching was used to evaluate suprathreshold visual perception under conditions which simulated the luminance, contrast, and chromaticity of third generation image intensifiers contained in the Aviator's Night Vision Imaging System (ANVIS). The apparent contrast of letters in this simulated ANVIS environment was reduced by a factor of two when compared to normal photopic levels of stimulation. This effect was attributed to limitations of the human visual system in processing higher spatial frequencies at low light levels. Theme results help to quantify and discriminate between visual and electro-optical limitations on vision through image intensifiers.... Night Vision Goggles, ANVIS, Contrast Perception.