| After years of development from creation to now, head-mounted display (HMD) is notonly becoming more common in the military field as an advanced digital equipment, but alsowidely applied to virtual manufacturing, medical, simulation training, entertainment andother fields, assuming an increasingly important role in the production and life.Whether full-input or half-input style of HMD, the performance of Relay optical systemdetermines the quality of helmet-mounted display to some extent. Most of detections on theHMD is generally on such aspects as brightness detection, optical axis calibration, imagequality testing. The total field of view of HMD, parallax measurements of each position areless involved. Aiming at detecting field of view and the parallax these two parameters ofrelay lens group of HMD, we use visual measurement techniques, coupled with electricdisplacement control mechanism, combined with the image acquisition equipment, buildfield of view and parallax detection system of helmet-mounted display.Through the image processing on the Reticle reticle image from Collimator, the CCDimage pixel location and its corresponding field of view angle is recorded. According toField and parallax detection principle, combined with electric displacement control system,do Collect field and parallax images. For the specific characteristics of the image, weanalysis and compare the methods of image preprocessing and edge detection, select properimage processing algorithms for the system. According to their corresponding target positiondetection algorithm, specified parameter values of field and parallax are calculated out.To improve the detection accuracy of the system, we study the corresponding sub-pixeldetection of a variety of means, and actively apply them to image processing which leading abetter detection accuracy. In addition, the factors that affect the detection accuracy wereanalyzed, and improved methods were proposed. |
