中国激光, 2015, 42 (6): 0608005, 网络出版: 2022-09-23
波长扫描激光器光谱线宽的动态测量技术研究
Dynamic Measurement of Linewidth of the Wavelength-Swept Lasers
激光器 光谱线宽 动态测量 可调谐环形腔激光器 半导体光放大器 lasers spectral linewidth dynamic measurement tunable ring laser semiconductor optical amplifier
摘要
波长扫描激光器是光纤传感和光学相干层析技术中的关键部件,其动态输出光谱特性决定了传感与成像系统的分辨率水平。采用改进的外差法和电光调制器(EOM)法对自制的波长扫描激光器的输出光谱进行动态测量,得到光谱线宽(反映光源的相干性)及其与波长扫描频率的关系。结果表明,输出光谱线宽随着波长扫描频率增大而增加,EOM 法比外差法测得的光谱线宽略大,波长扫描频率为60 kHz时,外差法测量激光器输出光谱线宽在4.9 pm,EOM 法测得为37 pm。<作者>
Abstract
Wavelength-swept laser is the key component for optical fiber sensing and optical coherence tomography, and its output spectral characteristics determine the resolution of the sensing and imaging systems.An improved heterodyne method and a direct measurement method by fast synchronous time gating with an electro-optic modulator (EOM) are proposed to dynamically measure the output spectra of a selfmade prototype of a ring cavity wavelength swept laser. The spectral linewidth, hence the coherence length of the laser source, are obtained to show its increasing dependence on the wavelength-swept frequency. The linewidth measured by the EOM method is greater than that of the heterodyne method due to the modulation, and the respective linewidth are 37 pm and 4.9 pm while the wavelength-swept frequency is 60 kHz.
王哲, 王智, 刘岚岚, 王甫, 余贶碌, 吴重庆. 波长扫描激光器光谱线宽的动态测量技术研究[J]. 中国激光, 2015, 42(6): 0608005. Wang Zhe, Wang Zhi, Liu Lanlan, Wang Fu, Yu Kuanglu, Wu Chongqing. Dynamic Measurement of Linewidth of the Wavelength-Swept Lasers[J]. Chinese Journal of Lasers, 2015, 42(6): 0608005.