Research On Laser Heterodyne Interference Microdisplacement Measurement System

Goos-Hanchen displacement plays a very important role in optical waveguide detection,optical communication and other fields.This displacement is very small,and it is very difficult to make measurements in experiments,which hinders the practical application in its field.Therefore,an improved method for measuring the displacement also continues to develop and innovate under this demand.In this paper,based on the analysis and study of laser heterodyne interference,Goos-Hanchen displacement,the development of PSD and the status quo,the system's overall scheme for measuring the displacement difference between p-light and s-light is designed.Firstly,the principle of laser heterodyne interferometry is described,and the improvement and innovation of the optical path structure are performed.The first-order diffracted light of p-light and s-light is used to synthesize and illuminate the coated prism.Selection and performance analysis of optical devices and components used in laser heterodyne interference optical paths.Secondly,the principle of the PSD displacement measurement system is expounded.The overall circuit of the PSD signal acquisition and processing system is designed and drawn.The device selection and noise reduction are performed for each module in the circuit,and the software part is written.Finally,the experimental process and experimental data of the system part and the whole are displayed.The system error is analyzed and the error is reduced as much as possible during the system design process.By measuring the light intensities of the system's original beam,p-light,and s-light,the brightness consistency of the p-light and s-light is verified.The heterodyne interference optical path noise test experiment results verify that the heterodyne interference optical path has better anti-jamming capability.Through communication port testing,PSD displacement measurement accuracy experiment and Goos-Hanchen differential displacement measurement experiment,the overall design feasibility of the system is verified.In the experiment process,the angle of the incident light at the prism is adjusted several times by rotating the platform,the position coordinates of the p-light and the s-light are respectively measured,the coordinate difference is solved,and the resulting graph is plotted.