Abstract
In this paper, some properties of the functional visual field are described. A loss of efficiency appears, when the display angle, covered by the task, exceeds certain boundaries. These boundaries appear to be related to the necessity to make eye and head movements in order to shift from one signal source to another. Some major aspects of theory experiments on the functional visual field are described and some applications are suggested. The subject appears to be very relevant to the optimal size of work panels and to the use of the visual field in automobile driving.