一种新型的专用于光学相干层析系统的宽带光纤光源

报道了一种新型的专用于光学相干层析系统的输出光谱为准高斯型的宽带超荧光光纤光源.该光源采用掺饵光纤作为增益介质.其关键技术是在抽运源的输出端增加了光耦合器，并在光源输出端插入多级长周期光纤光栅对铒离子的自发光谱进行调制和整形；同时采用光控器和温控器来控制抽运源的输出以提高光源输出功率的稳定性.该光源的中心波长为1.57μm，输出光谱的3dB带宽大于75nm，输出功率为27mW.实验结果表明，该光源输出光谱的自相关函数的旁瓣峰被大大削弱，可以满足光学相干层析系统的应用. 关键词： 光学相干层析术 超荧光光纤光源 长周期光纤光栅 光耦合器

A new broadband fiber light source for optical coherence tomography

A new type of Gaussian-like broadband superfluorescent fiber light source suitable for optical coherence tomography (OCT) is introduced in this paper. Erbium-doped optical fiber simultaneously pumped by 980nm laser diode (LD) and 1480 nm LD is used as the gain medium. Both optical controllers and temperature controllers are employed to adjust the output of LDs and to improve the stability of output power of light source. A fiber coupler with a specific splitting ratio plus multi-stage long period fiber gratings are used to modulate the output spectrum so that the spectral profile of the broadband light source is near Gaussian. The output power is about 27mW with center wavelength at 1.57μm and the bandwidth over 75 nm. The experiment results reveal that the sidelobes of the autocorrelation function of the output spectrum are effectively suppressed, which can meet the need of optical coherence tomography.