A visual field test measures how much central and 'side' vision you have. It is a straightforward test, painless, and does not involve eye drops. Essentially lights are flashed on, and you have to press a button whenever you see the light. Your head is kept still. The lights are bright or dim at different stages of the test. Some of the flashes are purely to check you are concentrating.
Each eye is tested separately and the entire test takes up to 15 minutes.
In our office the test is carried out by a computerized machine, called a Humphrey Matrix. For each test you have to look at a central point then press a buzzer each time you see the light.