At 2m, detection area is a circle of 4 m diameter
At 3m, detection area is a circle of 6 m diameter
At 4m, detection area is a circle of 8 m diameter
At 5m, detection area is a circle of 10 m diameter
At 6m, detection area is a circle of 12 m diameter
At 7m, detection area is a circle of 14 m diameter
At 8m, detection area is a circle of 16 m diameter
小幅移动检测区域（米）
At 2m, detection area is a circle of 3 m diameter
At 3m, detection area is a circle of 4.5 m diameter
At 4m, detection area is a circle of 6 m diameter
At 5m, detection area is a circle of 7.5 m diameter
