Abstract:  In view of the ubiquitous problems in tunable diode lasers, such as small tuning range of output optical frequency without mode hopping, low scanning frequency and complex structure, the dynamic characteristics of the internal piezo-based actuated systems of tunable diode lasers were studied. Based on the design goals of improving rotation accuracy and reducing axis offset, a multi-leaf parallel star-shaped flexible mechanism structure was proposed. After that, based on the Lagrange equation and Duhamel integral, the differential equation of motion and the vibration equation of the piezo-based actuated systems were respectively established.Then, the dynamics model of the flexible mechanisms was established and the structural parameters were optimized. Finally, a test platform was built to explore the mechanical response characteristics of the piezo-based actuated systems and the tunable range of tunable diode lasers. The experimental results show that the first-order natural frequency of piezo-based actuated systems is as 2187 Hz. The maximum axis offset of the flexible mechanisms is as 0.947 mm. In the mode-hop-free tuning performance tests of tunable diode lasers, a mode-hop-free tuning range of 103.5 GHz is achieved at a tuning frequency of 20 Hz. 

Key words: piezo-based actuated system, flexible hinge, optimal design, tunable diode laser

摘要： 针对可调谐半导体激光器中普遍存在的输出光频率无跳模调谐范围小、扫描频率低、结构复杂等亟待解决的问题，研究了可调谐半导体激光器内部压电驱动系统的动力学特性。基于提高回转精度、降低轴心偏移量的设计目标，提出了一种多叶片并联的星型柔性机构结构。基于Lagrange方程和Duhamel积分，分别建立了压电驱动系统的运动微分方程和振动方程，在此基础上建立了柔性机构的动力学模型并对其结构参数进行了优化。最后，搭建了压电驱动系统动态特性测试平台，测试了压电驱动系统的机械响应特性以及可调谐半导体激光器的输出光可调谐范围。实验结果表明，压电驱动系统一阶固有频率为2187 Hz，柔性机构最大轴心偏移量为0.947 mm。在可调谐半导体激光器无跳模调谐性能测试中，当调谐频率为20 Hz时，实现了103.5 GHz的无跳模调谐范围。

关键词: 压电驱动系统, 柔性铰链, 优化设计, 可调谐半导体激光器