Spatial and temporal resolution are two of the most fundamental characteristics of visual displays, and yet they are often incorrectly defined and specified. In order to address this problem, we have developed techniques for estimating both spatial and temporal resolution, and we have compared the resulting estimates to data obtained from perceptual tasks. The spatial resolution technique is based on a VESA standard (FPDM, Ver. 2.0), and was applied to several CRT displays. It was found that the pixel count does not adequately define display resolution when the former exceeds the bandwidth of the display device. In addition, the spatial resolution measurements were found to correlate well with perceptual assessments of the orientation of target aircraft simulated at various distances. The temporal resolution technique involved measuring the response of various displays to simple light patterns that could be flickered at up to 30 Hz. Data obtained for CRT projectors indicated that temporal artifacts obtained with these devices are due primarily to the limited frame rate of the image generator, rather than to limitations in the temporal response of the projectors. In addition, data obtained from liquid crystal on silicon (LCoS) projectors indicated that their on- and off-responses are short enough to support 60 Hz simulator frame rates, but that the hold-time used to maximize image luminance interacts with eye movements to produce temporal artifacts that can reduce the quality of the displayed imagery. The results of a perceptual test, based on the perceived separation of moving lines, were consistent with the measured temporal resolution of the two displays.

All measurement and analysis techniques described here have been implemented in a software package that is available from AFRL, Mesa, Arizona.