Paper
20 March 2020 Calibration method of conformal x-ray transmission imaging system based on small ball phantom
Author Affiliations +
Abstract
Compared to conventional X-ray transmission imaging techniques, imaging systems based on field-emissive cathode based conformal transmission imaging schemes have smaller volumes. This imaging system combines multiple point sources to complete very low dose imaging of the region of interest using a small cone beam, and finally obtain high quality images by image restoration methods. However, more precise system geometry is required by the system architecture of the new imaging scheme and the special image-forming method. If the geometric parameters that are inconsistent with the actual use are used in image restoration, it will cause the geometric distortion in the final restored image. In this work, a proposed geometric calibration applied to the new imaging scheme. First, we use a partial point source on the periphery of the array ray source to project the side ball phantom of the imaged object. Then, a cost function that associates the geometrical parameters with the degree to which the back-projections of the ball phantom in projections from different point sources is constructed. Finally, the particle swarm optimization (PSO) is used for minimizing the cost function, and the resultant value of the cost function is the actual geometric parameter. With this calibration method, transmission imaging and geometric calibration will be done simultaneously. Besides, this calibration method does not depend on a complex calibration phantom and is simple and effective. In addition, the PSO can accelerate the implementation of the algorithm. The effectiveness and accuracy of this calibration method are verified by two sets of simulation experiments.
© (2020) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Yang Li, Shaohua Zhi, and Xuanqin Mou "Calibration method of conformal x-ray transmission imaging system based on small ball phantom", Proc. SPIE 11312, Medical Imaging 2020: Physics of Medical Imaging, 113122B (20 March 2020); https://doi.org/10.1117/12.2549887
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Imaging systems

Calibration

Sensors

X-ray imaging

X-rays

Image restoration

Particle swarm optimization

Back to Top