secondary mirror

• 副镜

secondary mirror的用法和样例：

例句

1. A small error in secondary alignment is usually not a problem.
   副镜稍微有些偏离也问题不大。
2. You should center this fully illuminated area in the eyepiece by positioning the secondary in the correct location.
   你应该调整副镜的位置，直到在目镜里看到的明亮的区域位于中央。