Research On Precise Driving Technilogy Of 980nm Pump Laser

980nm laser-pumped erbium-doped fiber amplifier(EDFA)can effectively increase the 1550 nm band continuous laser and pulsed laser frequency comb power,so in optical communications,precise spectral analysis,size measurement and other fields play an important role.In many precise metering applications,the gain stability of the EDFA determines the stability of the laser power and the measured signal.Among the many influencing factors,the power stability of the 980 nm pump laser is the most critical factor in determining the EDFA power amplification stability.At present,the 980 nm pump laser is mostly butterfly-shaped semiconductor laser,the output of the laser power is mainly driven by the laser driving current and operating temperature directly.In order to solve the urgent need of high stability EDFA,this paper analyzes the mechanism of driving current and operating temperature on pump laser power from the working principle of 980 nm pumped laser.Based on this,a high stability driving current and operating temperature controller to achieve high power,high stability 980 nm pump laser and experimental verification.The main contents of this paper are as follows:(1)Aiming at the linear effect of the driving current of the pump laser on the output power,a high current precise constant current driving unit based on the deep negative feedback principle is developed.In order to avoid the laser being damaged,for the laser to open and the use of the process of step and impulse phenomenon,the paper has designed the slow start circuit.But also for the special circumstances of the high current impulse,designed overcurrent protection circuit.Finally,in order to ensure the stability of the laser output,the driver was insulated.(2)Aiming at the problem that the change of the operating temperature of the pump laser will cause the output power to drift,the working temperature control unit of the pump laser based on the precise temperature bridge is developed.In order to avoid the influence of noise in the circuit on the temperature measurement accuracy,the paper has designed a special low noise amplification and filtering links.Finally,the segmentation control algorithm is used to suppress the large inertia problem in the temperature control process.The experimental results show that the driver can realize the current output in the range of 0~1A and ensure the long-term current stability better than 100?A.In the range of 15~25?,it can realize the temperature control over 0.002? stability.The experimental results show that the power stability is 0.1% in the range of 0-200 m W of pump laser output power,which is better than that of existing ones.The experimental results show that the power supply of the S26-7402-200 980 nm butterfly pump is controlled by the above precise driver.Most domestic pumped lasers.The 980 nm pump driver was applied to the laboratory self-built EDFA system.With the 0.5m length Er110-4/125 erbium-doped fiber,under the reverse pumping condition,the laser power amplification of about 12 d B was realized,and we have realized the magnification stability of 0.92%.