Improvement of Wood CT Images by Consideration of the Skewing of Ultrasound Caused by Growth Ring Angle


  • Kwang-Mo Kim
  • Jun-Jae Lee
  • Sang-Joon Lee
  • Hwanmyeong Yeo


Ultrasonic wave, computed tomography (CT), transmission path, skewing effect, wave refraction, juvenile wood


For the purpose of removing distortions in ultrasonic computerized tomographic (CT) images of wood, this study proposes a technique for taking into account the skewing effect in reconstructing the image. First, it was experimentally confirmed that an ultrasonic wave is refracted because of the anisotropic characteristics of wood. Transmission paths of an ultrasonic wave through a cross-section of wood were predicted by considering the change in wave velocity based on the annual ring angle and the presence of juvenile wood. Then, the methodology of the application of the predicted paths to CT image reconstruction was proposed and verified. The accuracy of defect detection in wood was significantly improved by the proposed technique.


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