Abstract:A precise temperature control system based on adaptive digital proportion integration differentiation(PID) algorithm is presented to meet the requirement of 2 μm injected frequency-locked laser for frequency stabilization of the single frequency seed laser.According to the uncertainty of laser temperature variation,nonlinear compensation,digital filter,hardware isolator and component selection are used to guarantee the temperature control precision.On the basis of system design,the debug methods of Γ,Kp,Ki,Kd are discussed,and the oscillatory convergence waveforms of system control-voltage are measured.The system is applied to single frequency Tm∶YAG laser,the drift of laser frequency can be suppressed effectively.In observing time of 6 minutes,the offset of laser frequency is about 19.776 MHz,the frequency stability is approximate 1.31×10-7,and meets the requirements of 2 μm injected frequency-locked laser.The experimental results show that good stability and strong anti-interference can be gained and the temperature-controlling error of the system is about ±0.01 ℃ at 10~35 ℃.