用于皮秒种子锁模稳定检测的脉冲重频测量方法

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关键词：皮秒锁模激光器；脉冲重复频率；可编程门阵列；等精度周期测量；滤波处理 中图分类号： TM935.44 文献标志码：A DOI：10.12305/j.issn.1001-506X.2025.03.03

Pulse repetition frequency measurement method for picosecond seed mode-locked stability detection

ZHANG Zhenguo 1，2 ，MA Teng1，²，ZHUANG Mingjin1，LI Mingshan ， MENG Dongdong1，FAN Zhongwei²，* （1. Aerospace Information Research Institute， Chinese Academy of Sciences，Beijing lOoo94，China; 2.University ofChineseAcademyofSciences，Beijinglooo49，China）

Abstract：Aiming at the problem of seed-source mode-locked stability monitoring of picosecond lasers，a digital measurement systemof laser pulserepetition rate based on field programmable gatearray（FPGA）is designed.The systemuses multiplephase-shifted high-frequency standard clock signals generated by the phase locked loop（PLL）ofFPGA to count and measure the time gate generated by the input optical pulse signal，and uses the method of amplitude limiting filter and arithmetic average filter to obtain moreaccurateand stable frequency measurements to strengthen the anti-jamming ability of the system.The proposed system measures the signal to be measured at 80MHz ，the theoretical measurement accuracy can reach 31.7Hz ，and the relative accuracy can reach 3.96×10-7 .According to the experimental test results，the actual accuracy is about 18Hz ， and the relative accuracy is 2.25×10-7 ，the system design is verified to meet the accuracy requirements.The result shows that the proposed system can accurately sense the repetition frequency change of picosecond seed laser pulse in MHz ，which provides a basis for further judgment and control of mode-locked stability，and also has significant reference value for other industrial frequency measuring devices design.

Keywords：picosecond mode-locked laser；pulse repetition rate； field programmable gate array （FPGA）； equal precision periodic measurement；filter processing

0 引言

激光锁模技术广泛应用于产生超短脉冲激光，目前通过锁模可以实现皮秒甚至飞秒量级的脉冲激光输出[1-2]。（剩余14733字）