• Laser & Optoelectronics Progress
  • Vol. 60, Issue 16, 1615004 (2023)
Xudong Lin and Xu Zhang*
Author Affiliations
  • School of Mechanical and Automotive Engineering, Shanghai University of Engineering Science, Shanghai 201620, China
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    DOI: 10.3788/LOP222259 Cite this Article Set citation alerts
    Xudong Lin, Xu Zhang. Accurate Camera Calibration Method Based on Perspective Distortion Correction[J]. Laser & Optoelectronics Progress, 2023, 60(16): 1615004 Copy Citation Text show less

    Abstract

    Traditional camera calibration methods with a circular array target typically use the center of the ellipse as the control point coordinate, ignoring distortion from projective effects and introducing systematic errors into the calibration process. Therefore, we propose an accurate camera calibration method based on perspective distortion correction. Herein, first, the camera was coarse calibrated using the center of the ellipse. Second, using the coarse calibration parameters, the projective transformation corresponding to the camera's pure rotation was determined, and the ellipse parameters were directly changed to yield the true projected center of the circle. Finally, we used the obtained center to perform fine camera calibration. According to the simulation and experimental results, the suggested technique significantly reduces the reprojection error and parameter standard deviation of camera calibration; it can meet the simple, high-precision criteria of camera calibration for industrial vision measurement.
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