photoelectric length meter

例句：

1. 1. The photoelectric length meter is used to measure the distance between two points in space.
   光电长度计用于测量两个点之间的距离。
2. 2. The photoelectric length meter is a crucial tool for surveying and mapping.
   光电长度计是测绘工作中不可或缺的工具。
3. 3. The photoelectric length meter has greatly improved our ability to measure distances accurately.
   光电长度计大大提高了我们测量距离的准确性。