单偏振半导体光放大器扫频光相干层析系统

Optical Coherence Tomography System Based on a Polarization-dependent Semiconductor Optical Amplifier-enabled Swept Laser

摘要:

实现了基于单偏振半导体光放大器高速扫频光源的光相干层析系统。系统中的扫频光源使用偏振相关的半导体光放大器, 采用傅里叶域锁模结构。偏振相关的半导体光放大器有着增益谱宽大、输出功率高的优点, 使得光源仅使用一个放大器即可获得足够的增益谱宽与输出功率。扫频光源输出功率达到32mW左右, 有效扫描频率为45kHz, 输出光谱的中心波长为1326nm, 光谱宽度为115nm。利用系统进行光相干层析成像时, 横向分辨率为9μm, 纵向分辨率为12.9μm左右, 灵敏度为105dB。利用该系统实现了多种生物和非生物样品的光学相干层析成像。

Abstract:

In this paper, demonstrated is a swept-source optical coherence tomography (OCT) system based on a polorization-dependent semiconductor optical amplifier (BOA)-enabled high-speed swept source. The swept source has a Fourier-domain mode-locked (FDML) structure with a BOA as the gain medium. Attributed to the broad bandwidth and high saturation power of the BOA, the swept source can provide sufficient spectral width and output power with only one amplifier. The swept source generates 32mW output power at 45kHz sweep rate, with a tuning range of 115nm centered at 1326nm. On top of the swept source, an OCT system is built with axial resolution of 12.9μm, transverse spot size of 9μm and sensitivity of 105dB. OCT images of various biological and non-biological samples are presented.