基于法布里-珀罗调谐滤波器的傅里叶域锁模扫频激光光源

摘要

An all-fiber Fourier domain mode locking (FDML) swept laser source at 1300 nm for swept source optical coherence tomography is reported. The swept laser source is realized with power amplification and laser resonator which includes gain medium, tunable filter and dispersion managed delay line. FDML swept laser can realize high-speed tuning, and phase is stable since its highly stable mode locking operation. The turning range of fiber Fabry-Perot tunable filter (FFP-TF) based FDML swept laser is 130 nm, and the 3 dB bandwidth is 70 nm with an average output power of 11 mW. The tunable speed of FDML laser is 48.12 kHz compared with 8 kHz of short-cavity FFP-TF based swept laser. The axial resolution in OCT imaging of FDML swept laser is 7.8 µm (in tissue), which is improved by 1.9 µm compared with that of short-cavity swept laser.%　　报道了一个光纤型1300 nm波段的傅里叶域锁模(Fourier domain mode locking, FDML)扫频激光光源,用于扫频光学相干层析成像技术(optical coherence tomography, OCT)成像.本实验扫频激光光源采用包含增益介质、调谐滤波器和延迟线组成的长腔激光谐振腔以及光功率增强单元. FDML扫频激光光源具有快速和高度稳定运转模式,相位稳定性好.基于法布里-珀罗调谐滤波器(fiber Fabry-Perot tunable filter, FFP-TF)的FDML扫频激光光源扫频范围为130 nm,半高全宽为70 nm,输出平均功率是11 mW.与基于FFP-TF的短腔的扫频光源做了对比研究, FDML扫频光源速度从短腔的8 kHz提高到了48.12 kHz,对应生物组织OCT成像轴向分辨率为7.8µm,比短腔的减小了1.9µm.