Instruments for measuring visual fields including a portable perimeter having a handle by which it can be held by the subject being tested. In a preferred embodiment, the perimeter includes a protractor which can be rotated clockwise-counterclockwise about an antero-posterior axis to any desired meridian. One end of a cord is attached to the protractor and a light source is attached to the other end of the cord. The protractor has angular markings thereon and the examiner uses the relationship of the cord to the angular marks and the meridian orientation of the protractor to determine the response of the eye to the light source. The protractor also can be rotated antero-posteriorly about a horizontal axis so that the same perimeter can be used to measure the response of both eyes merely by turning it over. A marking pad is provided to or upon which the response of a patient can be indicated when viewing the light source as it is moved through various angles of the field. In another embodiment of the invention, the angular field to be viewed is located on a chart held at a fixed distance from the perimeter and a light source is moved in front of or behind the chart.
Instruments for measuring visual fields