In this paper, visual search performance for tactical symbols was examined with liquid-crystal (LCD) and cathode-ray tube (CRT) displays. 24 participants searched for navy tactical display symbols on a map background. LCD and CRT displays of similar size and resolution were used. Viewing angle (0 deg. vs. 60 deg. of azimuth), set size, target colour (blue, white, red) target presence, and search type (feature vs. conjunction) were also manipulated. Participants showed reduced sensitivity for red and blue symbols viewed 60 deg. off axis with the LCD relative to on-axis LCD, or to the CRT on or off axis. Coloured symbols viewed off axis on the LCD produced longer response times in feature search and lower search efficiency in conjunction search. Results argue against the use of current LCD technology when off-axis viewing is likely and colour coding is used. (Author/publisher)
Abstract