The Effects of Color and Contrast on Target Recognition Performance Using Monochromatic Television Displays.

Abstract : White, green, and red monochromatic television phosphors are used in a variety of military display systemns, without consideration to their potential effect on an operator's target recognition performance. Since display contrast is known to have a significant effect on target recognition performance, it was also included as a variable to examine possible interaction effects. Target recognition performance was operationally defined as the visual angle (degrees) subtended by a group target, viewed via a television, at the time of recognition. Each of the twelve subjects viewed five different types of targets at four diagonal orientations, each under six television display conditions. For each trial, the target (located in the center of the television) started small and unrecognizable, then slowly enlarged until it became recognizable. At the moment of recognition, the subject pressed a projector stop button and identified the target. The experimenter then measured the target's size. Results showed that color did not significantly affect subject's target recognition performance (p = 0.25). Contrast was highly significant (p 0.001), thereby replicating several previous studies. There was no color by contrast interaction (p = 0.70), but targets and color by targets were significant (p 0.0001 and p 0.02, respectively).