Visual Sampling on a Simulated PPI Display

Much effort has been spent in studying the sonar operator as a target detector. In general, it is assumed that the operator samples all the data available to him. This sutdy discusses the operator's sampling procedure on a simulated plan position indicator (PPI) display. In visual sampling, information is obtained by an operator from a display by fixating points on the display with his eyes. The area near these points contains most of the information that the operator uses from the display to make a decision of 'target' or 'no target'. The use of the Electro-oculargram(EOG) is obtaining the operator's fixation points is discussed, along with the drift problems and a method to decrease drift by using feedback to the electrodes. Experimental results of an operator's sampling of a simulated PPI display are reported for two types of CRTs: storage and nonstorage. (Author)