The Study On The Pointing Stability System Of Laser-beam

With the continuously expanding of the optical system in application area, optical system designer are still obsessed by dynamic interferences. The paper mainly introduces the laser beam pointing stabilization system from the optical design to the final realization of the laser beam pointing stabilization. The light path mainly includes PSD and the FSM system (FSM-300and FSM-CD300B).For the servo control system, the accuracy of the given data directly decides the final result of the control system. The main point of the laser beam pointing stabilization system is the detection of the signal spot. PSD is a kind of analog device, and it is a position sensing device utilizing the lateral photoelectric effect that produced by the semiconductor junction. PSD is a kind of optical sensor that can detect the "center of mass" of the incident light. This experiment chooses a PSD produced by the Sitek corporation in Sweden, model number is2L10_SU65_SPC02. PSD measures the position error of the light in two dimensions. We will analyse the position error that caused by the interference light,then give some conclusions.Compile a C program under the DOS operating system Borland C++3.1builder, output a sine signal through the D/A output of A823PGL, the frequency are1Hz,10Hz,50Hz,100Hz. It is a checking for the operating characteristic of the FSM system. A mathematical model should be build for the servo control system. The way of PI control is adopted, the control parameters are adjusted according to the overshoot and the steady state error. The mirror of the FSM-300controls the incident light to the center of the PSD achieving the purpose of stabilizing the light.