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PERIPHERAL VISUAL FIELD TEST
While people tend to focus on whatever our eyes look directly at, we can also see objects on the sides of our field of vision. This viewing area is known as our peripheral vision. Visual field tests evaluate our peripheral vision.
Several types of peripheral visual field tests exist. They include the following:
Automated perimetry. You look into a special machine and focus on a spot in the center. You press a button any time you see a light flash in your peripheral vision.
Tangent screen exam. You focus on a target at the center of a screen. Your eye doctor moves objects in and out of your peripheral vision, and you indicate when you can first see them and when they vanish from your field of view.
Confrontation visual field exam. Your eye doctor sits opposite you and moves his or her hand into and out of your peripheral vision. You say when you see the hand and how many fingers your optometrist is holding up.
Each test allows an optometrist to identify gaps in your peripheral vision and determine the size of your visual field.