VISUAL FIELD ANALYSER

Typical Number in Hospital:

Cost Bands:

References:

The subject places his chin on a rest, and the eye to be tested is focused on a white disc in the centre of the apparatus. A second fixation target is slowly moved in from the periphery of vision and the subject indicates when he first sees it. By moving the second target in from different directions it is possible to plot isopters on a graph of visual field. Refinements include automatic mapping and circuits to detect if the eye wanders from the main fixation target. The device is also known as a perimeter.