backsight t回视
Backsight Reading后视读数
backsight method[测] 后视法
backsight point后视点
backsight distribution表尺分配
no backsight surveying无后视方向细部测量
Backsight video camera后视摄像机
tangent drum backsight鼓形表尺
variable aperture backsight可变孔径的照门
N（名词） the sight of a rifle nearer the stock (枪之)表尺缺口