中国激光, 2016, 43 (9): 0904007, 网络出版: 2018-05-25
光源混合频率调制的光热干涉工作点无源控制方法研究
Passive Work-Point Control Method for Photo-Thermal Interferometric with Mixing Frequency Modulation of Light Source
光电子学 光热干涉 相位漂移 无源 正交工作点 混合频率调制 optoelectronics photo-thermal interferometry phase shifting passive quadrature work-point mixing frequency modulation
摘要
提出了一种光源混合频率调制的闭环工作点无源控制方法,通过直接高频调制光源的方式从单路干涉信号中提取出相位漂移信号,并利用低频控制信号对光源直接调制的方式予以补偿。通过高频、低频调制信号的配合,解决了单路干涉信号的工作点跟踪问题,以无源控制的方式保证干涉测量系统始终工作在最灵敏的线性区域。测试了光源在不同调制频率下的调制特性,比较了系统开、闭环状态下工作点的变化趋势,无源闭环工作点控制法与相位载波解调算法的对比解调结果表明,两种方法解调结果相关度超过99%,证明该方法可行。
Abstract
The closed loop passive work-points control method is introduced for mixing frequency modulation of light source. The phase-shift signal is picked up from single interferometer signal by directly high frequency modulating light source, and compensated by the low frequency control signal with directly modulating light source. The problem of work-point tracking is resolved by the cooperation of high and low frequency modulation, the system is always working in the most sensitive linear region by way of passive control. The modulation characters of laser source are tested under different frequencies, and the variation tendency of work-point under open-closed loop is compared. Demodulation results of closed loop passive work-points control method and phase carrier demodulation algorithm show that the demodulation relevancy of two methods is above 99%, which proves the feasibility of the proposed method.
李树旺, 邵士勇, 梅海平, 饶瑞中. 光源混合频率调制的光热干涉工作点无源控制方法研究[J]. 中国激光, 2016, 43(9): 0904007. Li Shuwang, Shao Shiyong, Mei Haiping, Rao Ruizhong. Passive Work-Point Control Method for Photo-Thermal Interferometric with Mixing Frequency Modulation of Light Source[J]. Chinese Journal of Lasers, 2016, 43(9): 0904007.