Design And Facture Of600mW Laser Pump Source Control System

With the development of optical fiber communication technology in recent years,the application scope of erbium-doped fiber amplifier (EDFA) is increasinglywidespread. In order to meet the need of high power and stability for EDFA,600mWlaser pump source control system is designed and produced in this paper. The controlsystem integrates two functions include semiconductor drive and temperaturecontrol, and makes the common laser pump modules as the application object. Designthe circuit by matching the parameters of pump module, then form a complete laserpump sources. Laser pump module is a kind of butterfly devices packaged byhigh-power laser diode (LD) and thermoelectric cooler (TEC).In the paper，the drive unit of laser pump source control system is designed by usingthe principle of constant current excitation, then the temperature control unit of laserpump source control system is designed by using TEC as the temperature control meanat first. Second, the relevant electrical experimental tests of drive and temperaturecontrol unit are done, the tests include stability test of drive current, simulation test ofdrive unit, temperature control capability experiment of temperature control unit.Finally, a complete laser pump source prototype is produced by choosing a laser pumpmodule, and the laser output of the prototype is studied in detail. The tests includerelationship test of output optical power and drive current, stability test of opticalpower, stability test of spectral.After testing, the drive current range of laser pump source control system is0to1A.At the condition of0.6A output current, one hour short-term stability is508ppm andeight hours long-term stability is1448ppm. The maximum temperature control outputpower is10W. After that, the output of laser pump source prototype is tested. It showsthe optical power can reach600mW, the center wavelength of the laser pump sourceprototype is975.2nm, short-term power stability of the light is±0.008dB at thecondition of150mW output optical power, long-term stability of the optical power is ±0.05dB at the condition of400mW output optical power.The unique work of this article mainly includes:1. According to EDFA’s actual requirements of the laser pump source， thesemiconductor drive technology and temperature control technology were set in thesame control system which has strong practicability；2. Designed the circuit structure of the laser pump source control system for the driveunit and temperature control unit reasonably. The control system we produced hashigh driving stability and temperature control capability；3. Comprehensive consideration of the practical requirements of laser pump module,the control system also has good portability. It can match different laser pumpmodules by fine-tuning the circuit design, expanding the scope of application.Compared with similar laser pump source, the laser pump source prototype has ahigh degree of stability and reaches the high-end level of the market productsbasically. It indicates the600mW laser pump source control system can meet thedesign requirements. The control system that designed and produced in this article hassome practical value.