Fig. 1. Schematic diagram of MOPNA system based on all polarization maintaining fiber: (a) Oscillator; (b) amplifier; (c) compressor.全保偏光纤MOPNA系统结构示意图　(a)振荡级; (b)放大级; (c)压缩级

Fig. 2. Experimental setup for frequency doubling.倍频光路结构示意图

Fig. 3. The oscillator output: (a) Spectrum curve; (b) autocorrelation curve; (c) pulse sequence.振荡器输出锁模脉冲特性　(a)光谱; (b)自相关曲线; (c)脉冲序列

Fig. 4. Variation of the spectrum profiles under different pump powers of the pre-amplifier.预放大级不同抽运功率下的光谱变化

Fig. 5. The relationship between output power and pump power of the pre-amplifier.预放大级输出功率与抽运功率的变化关系

Fig. 6. The autocorrelation curve of pre-amplified pulse corresponding to pump power of 50 mW.预放大级抽运功率为50 mW时对应的脉冲自相关曲线

Fig. 7. The relationship between output power and pump power of the main amplifier.主放大级输出功率与抽运功率的变化关系

Fig. 8. The spectrum output from the main amplifier.主放大级输出光谱

Fig. 9. The pulse widths versus output powers and the lengths of compression fiber.不同输出功率下的最短脉宽及其对应的压缩光纤长度

Fig. 10. The optical spectrum: (a) Autocorrelation curve; (b) recompressed pulses.压缩级输出脉冲特性　(a)光谱; (b)自相关曲线

Fig. 11. The spectrum of second harmonic.二次谐波的光谱