大口径磁光隔离器隔离度单次测量技术

Single-Shot Isolation-Rate Measurement for Large-Aperture Faraday Rotator

搭建了全光纤化的大口径磁光隔离器隔离度单次测量系统,体积小且调节灵活方便,在大口径隔离器的在线测量方面具有独特优势。利用光纤器件在光束传输和耦合方面的优势以及磁光隔离器的工作特点,采用透过率相对测量法和静动态对比法实现了隔离度的单次测量。实验可测量动态范围达到33dB以上,且通过调整光纤耦合器分光比可使测量动态范围进一步提高到50dB以上。该方法有效消除了输入信号脉冲功率及偏振态抖动等因素对测量精度的影响,在输入信号脉冲能量和偏振态随机抖动的情况下,仍然可实现抖动波峰波谷(PV)值为2.2%的测量精度。

An all-fiber Faraday rotator isolation rate measurement system is designed and realized. The system has tremendous advantage for large aperture Faraday isolator on-line measurement due to its flexible alignment and more compaction. Employing the method of relative transmission measurement and transmissions contrasting between static and operating states, single-shot isolation-rate measurement is achieved. The available measurement range larger than 33 dB is demonstrated experimentally. And the potential to get measurement range larger than 50 dB by adjusting the coupling rate of the fiber couplers is affirmed. Measurement accuracy of 2.2% of PV value is achieved even while keeping the input pulse energy and polarization in random vibration, which illustrates that the influence of the input pulse energy and polarization vibration on the measurement aeeuracv is eliminated