Fiber Laser Stable Power

Based on the character of the Erbium-doped fiber gain at 1550 nm, the ring-cavityErbium-doped fiber laser in this paper, by using 980nm semiconductor laser asdiode-pumped, Erbium-doped fiber as gain medium, Bragg fiber grating as resonantcavity reflector, has gotten output with 1551.9 nm, a bandwidth of 0.06 nm at 3 dB。The focus of the thesis is to analyze and research into the noise caused by thering-cavity Erbium-doped fiber laser influenced by the relaxation oscillions. The thesishas surveyed the relationship chart of the relaxation oscillions phase and the frequency,and that of gain and frequency, put forward the specific plan to inhibit the relaxationoscillions noise with the help of PID negatively electronic feedback, and surveyed therelative intensity noise before and after controls.The thesis has analyzed the factors influencing the output power of the ring-cavityErbium-doped fiber laser and studied its stability starting with the control to stability ofdiode-pumped 980nm semiconductor laser and the inhibition to the noise caused by therelaxation oscillions. Also, the paper has designed and produced high accuracy stablecurrent-source with high precision reaching 0.02mA .An automatic temperature controlcircuit of LD, which is based on ADN8830 is introduced. The characteristics andapplied circuit of the chip are discussed in detail and the automatic temperaturecontrolling system reaching 0.01℃. Finally the experimental test shows that stability ofoutput power of the ring-cavity fiber laser can reach 0.01 dB which is superior to0.02～0.05 dB available in the market.