Design And Development Of Automatic Collimation System For Optical Path

In today’s optical experiments,with the increasing number of optical components and the increasing complexity of the system structure,it is difficult to guarantee the reliability and maintainability of the system.Therefore,this presents a severe challenge to the experimenters’ fine degree in manual adjustment.To solve the above problems,more and more optical experiments begin to gradually integrate electric control components into the system structure to reduce the difficulty and error of manual adjustment.Under this background,optical path automatic collimation technology comes into being.In the optical path automatic collimation system,the collimation time and accuracy are the two most critical factors.This paper designs an optical path automatic collimation system based on four-quadrant detector by comparing the implementation methods and advantages and disadvantages of the previous automatic collimation system.The system includes three parts: data acquisition module,data analysis module and feedback control module.(1)According to the acquisition principle of four-quadrant detector,the design of data acquisition module is completed.The data acquisition module consists of four quadrant detector and NI PXIe-1082 data acquisition card.Based on the hardware configuration,a real-time spot location acquisition program based on LabVIEW was designed.The collection program is developed according to DAQmx driver framework,which can save the collected data in the format of csv file.The experiment of the test platform shows that the acquisition program can run in Windows 7 SP1 or above operating system,and meets the performance requirements of the optical path automatic collimation system.(2)Complete the design of data processing module based on Python.Pandas and other tools are used to read and pre-process the collected data.Then the simulated annealing algorithm is introduced to carry out the iterative operation,and the result of the iterative operation is feed back to the automatic control module through the Python program.(3)According to the return result of the data processing module,the feedback control of the electric frame is realized.The return value of Python program is read by using the API related to the operation command line in C# language,and then 8742-4-KIT travel drive controller is controlled by the feedback step size in the return value,and then the Model 8807 electric frame is driven to complete the calibration of the beam direction and complete the closed-loop feedback of the system.(4)The collimation performance of the system is tested by building an optical test platform.After repeated experiments,it is determined that the single collimation time of the system is less than one minute,the system angular resolution is 0.7μrad,The average collimation error from the center of the spot is 3.77μm in the horizontal axis and 3.49μm in the vertical axis.