cross-hair eyepiece

例句：

1. 1.The scientist used a cross-hair eyepiece to measure the distance between two objects.
   科学家使用十字准星目镜来测量两个物体之间的距离。
2. 2. The artist focused his cross-hair eyepiece on the painting for hours.
   艺术家用他的十字准星目镜聚焦在这幅画上几个小时。
3. 3.The engineer used a cross-hair eyepiece to adjust the focus of his camera.
   工程师用十字准星目镜调整了他的相机的焦点。