Rate-dependent input curve shaping of the piezoelectric actuator based optical resonator cavity displacement characteristics for an external cavity diode laser.

In an external cavity diode laser, the rate-dependent nonlinearity of the piezoelectric actuator based optical resonator cavity (ORC) restricts its application in high-precision measurements. This paper proposes a rate-dependent nonlinear active suppression method for an ORC system based on the Hammerstein model. Using a back propagation neural network and system identification algorithm, a high-precision rate-dependent Hammerstein model of the ORC system is established. The B-spline curve is used to simplify the input voltage curve, and the optimized voltage curve that can obtain the linear displacement output is solved by the particle swarm optimization algorithm. The experimental results show that in the frequency range of 2-50 Hz, the regression coefficients (R) of the ascent and descent stages at each experimental frequency of the ORC system increased to over 0.9998 and optimized the curve at the inflection point to suppress the vibration at the inflection point.