A perimeter for examining a visual field condition of an examinee's eye, includes: a target presenting unit a response unit brain activity detecting unit which detects an activity condition of a visual cortex of the examinee; and an operation unit which determines if the response with the response unit with respect to presentation of the target is resulted from a fact that the examinee can perceive the target based on a detection result of the brain activity detecting unit and which obtains the visual field condition on the basis of the presentation condition of the target and the response result in consideration of the determination result of the brain activity detecting unit.
Perimeter