Design And Research On The Parameter Comprehensive Measuring Instrument Of Annular Parabolic Mirror

The toroidal parabolic mirror is the key optical element of the optical system such as the positioner.In this paper,a measuring instrument for comprehensively measuring the focus quality,focal length and eccentric angle of a toroidal parabolic mirror has been successfully developed.The measuring instrument can simultaneously measure multiple parameters such as the focal length of the annular parabolic mirror,the center of the diffuse spot,the size of the diffuse spot,the size of the deflection angle to meet the measurement requirements of the production site.Based on measurements taken herein collimator embodiment,the measuring structure is simple embodiment,the measurement results are directly related to a method and system applications,the specific contents are as follows:(1)This article analyzes the technical status of focal length measurement,the measurement of the size of the dispersion spot,the measurement of the center of the dispersion spot,and the measurement method of the deflection angle.A comprehensive measurement plan was proposed,and the relevant parameters of the measurement plan were clarified.(2)This paper proposes a scheme based on collimator to measure focal length,spot center,spot size and deflection angle.According to the measurement plan,the optical system,motion system,and information acquisition system in the measurement system are analyzed to obtain the design requirements of related devices.Analysis of the meter mechanical error caused by the turntable angle measurement error,error correction and provide ideas for reducing the mechanical structure precision turntable.(3)This paper simulates the deflection angle measurement based on the measurement scheme.The simulation results verify that the declination angle calculation formula is applicable when measuring small angles.The mechanical position error and mechanical angle error of the rotating table are analyzed,and the method of 180° flipping twice to eliminate the angle error of the rotating table and reduce the mechanical structure accuracy requirements of the rotating table is proposed and related formulas are derived.According to the non-deflection angle reflector,the deflection angle measurement result is further calibrated and the calibration formula is derived.(4)According to the determined measurement system scheme,suitable devices were selected and some devices were improved.With the development of the measuring instrument software operating system,the assembly and debugging of the measuring instrument have been completed.(5)A standard lens with deflection angle and no deflection angle was used to verify the measuring instrument.The field application results prove that the relative error of the measured focal length is within 0.1%,and the spot size measurement meets the design requirements.For the measurement of deflection angle,the method of eliminating the angle error of the rotating table by 180° flipping twice can greatly reduce the accuracy requirements of the mechanical structure of the system,while ensuring that the relative error is within 4.1%,which verifies the accuracy of the measurement method.The measurement result of the deflection angle is further calibrated,and the error of the measurement result is less than an angle resolution,which shows the accuracy of the measuring instrument.