报道了一种基于光栅多面镜调谐滤波器的宽带快速线性扫频激光光源。调谐滤波器由光栅和旋转多面镜组成,采用了非望远镜型利特罗布局,以简化滤波光学系统。在激光谐振腔中采用了自发辐射光谱范围互为拓展的双半导体光放大器,并将二者并联使用以确保宽光谱范围。研制的扫频激光光源的中心波长为1312 nm,扫频光谱范围为170 nm,半峰全宽为116 nm,对应于多面镜695 r/s的转速,扫频速度达到50 kHz,相应的激光输出平均功率为2 mW。该宽带快速线性扫频激光光源,尤其适用于高分辨扫频光学相干层析成像系统,轴向分辨率能达到6.5μm。
A broad-band high-speed linearized swept laser source based on grating/polygon mirror tunable filter is reported.In order to facilitate the filtering system,the tunable filter consists of polygon scanner and grating in Littrow telescope-less configuration.Parallel implementation of two semiconductor optical amplifiers with different wavelength ranges is adopted in the laser resonator for broad-band light amplification.Center wavelength of the developed swept laser source is 1312 nm with a turning range of 170 nm and 3dB bandwidth of 116 nm.A repetition frequency up to 50 kHz with an average output power of 2 mW is realized while the polygon is scanned at a speed of 695 r/s.This high-speed broad-band linearized swept laser source is especially applicable to high resolution swept source based optical coherence tomography,of which the axial resolution can reach to 6.5 μm.