To begin the test, you will be asked to cover one eye, fixing your gaze on the examiner's eyes. The examiner will then conduct finger movements, bringing his or her hands into your visual field from the sides. Because your vision is divided into four quadrants in your brain, the examiner will hold up fingers in each quadrant. You will say how many fingers you see without actually looking at them, thus testing your peripheral, or side, vision.
Besides measuring your field of vision, the confrontation visual field test is also useful for detecting blind spots and eye diseases, as well as other health problems.
Choplin, Neil T and Russel P. Edwards. Humphrey Field Analyzer. SLACK Incorporated, 1995.