four-level laser rod

例句：

1. 1.This four-level laser rod is used for precise measurements in the field of optics.
   这根四级激光棒用于光学领域的精确测量。
2. 2. The engineer used this four-level laser rod to test the stability of the new machine.
   工程师使用这根四级激光棒来测试新机器的稳定性。
3. 3.In the manufacturing process, the four-level laser rod is crucial for ensuring precision and accuracy.
   在制造过程中，四级激光棒对于确保精度和准确性至关重要。