The stimulus (1) is presented as part of the background of the perimeter of a test person at pre-determined test localities. The stimulus has at least two visual properties which can be changed to determine a threshold value. The stimulus is formed by sinusoidal waves which widen out coaxially with a center (3). The total brightness is identical with the brightness of a background (2). The amplitude of the annular wave peaks (4) and troughs (5) diminish towards the periphery.
Stimulus for determining the perimeters o f the human eye's field of vision, involves sinusoidal waves with amplitude of troughs and peaks, and background brightness