Display Parameters Comprehensive Test System For Helmet Mounted Display

Because Helmet-Mounted Display(HMD)can cooperate with the combat carrier to achieve precisely strike,and has the advantages of easy operation and portability,it has been rapidly developed and become the basic configuration in modern combat systems.HMD playing an important role in the combat system that makes it becomes an important aspect to describe the national defense level.An important indicator for evaluating the development level is the display performance.How to accurately and objectively evaluate the display performance becomes the development of sights.A test system has been proposed in this article,which can test outlet aperture,pupil distance,field of view,parallax,double eyes parallax,distortion,character brightness,character line width and transmission rate et al,to complete the assessment of sight display.This paper focuses on the design of the test system,parallax image testing technology and line width curve fitting test technology.The main research of this article as follow:1.Design the overall HMD test system based on vision measurement.On the basic of the predecessors,fully understand the existing test methods for each test indicator.A fully automatic test plan for three-station division of labor is proposed.Selecting the main hardware model of the project.Introducing the design of the test software,and two key steps of the initial plane adjustment and finding the pupil flat are used to unify HMD coordinate and test system coordinate.2.The design of parallax test technology based on image process.A calibration method for a camera at infinity focal length is proposed.Thinning image features with a new layered thinning algorithm.The Shi-Tomasi corner extraction algorithm is used to extract the corners,and three high precision corner extraction methods are proposed and experiment verification.The error analysis is performed on the parallax test result,and the reliability and stability of the parallax test method is comprehensively evaluated.3.Design HMD line width test method based on Gaussian curve fitting.The luminance data is collected by a single pixel scanning method and preprocessed.According to the Gaussian distribution of the luminance on the aiming line,the Gaussian fitting by the least squares method is performed on the luminance data which is collected by image brightness meter.In order to decrease the fitting error,construct the nonlinear optimization objective function and use Levenberg-Marquardt algorithm to quadratic fit.The error analysis of the line width measurement result is performed,and the reliability and stability of the line width test method is comprehensively evaluated.