If possible a test should be performed in a quiet room, free from distractions.

Ambient lighting

Ambient lighting should be "subdued" and care should be taken to avoid reflections on the screen or any glare sources in the vicinity of the screen.

Refractive correction

The patient should wear an appropriate refractive correction for the viewing distance (including a reading Add for presbyopic patients).  Single vision spectacles may be worn provided the frame is sufficiently large and does not occlude any part of the screen.  Multifocal spectacles are not appropriate.


Large aperture "perimetry" lenses or full aperture trial lenses are preferred.

Head/eye position

It is important that the eye being tested is at the correct viewing distance (as defined in the setup) and approximately centered with respect to the screen.  A tape measure should be used to ensure the patient is at the correct viewing distance and that this distance is maintained throughout the test.


A chin/headrest is desirable to maintain the correct viewing distance and position.