Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Cone beam CT system geometric parameter calibration model and method

A technology for geometric parameters and correction models, which is used in medical science, diagnosis, computed tomography scanners, etc., and can solve the problems of reconstructed image artifacts, reconstructed image distortion, and low accuracy of geometric parameter solutions.

Active Publication Date: 2016-10-12
CHONGQING UNIV
View PDF10 Cites 10 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the point-shaped model has severe distortion in the reconstructed image obtained under the CT system with geometric errors. This problem will lead to low accuracy of geometric parameters in the micro-nano CT system that requires high resolution, thus Artifacts appear in the reconstructed image

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Cone beam CT system geometric parameter calibration model and method
  • Cone beam CT system geometric parameter calibration model and method
  • Cone beam CT system geometric parameter calibration model and method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0025] The preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings; it should be understood that the preferred embodiments are only for illustrating the present invention, rather than limiting the protection scope of the present invention.

[0026] figure 1 Schematic diagram of wireframe model structure; figure 2 Schematic diagram of projection of cone-beam CT system with ideal geometry; image 3 Schematic diagram of projection of cone-beam CT system with non-ideal geometry; Figure 4 Calibration method flowchart; Figure 5 Front view under non-ideal structure; Figure 6 yes Figure 5 side view of Figure 7 yes Figure 5 top view of Figure 8 yes Figure 5 side view of the other side; Figure 9 Schematic diagram of the relationship between angle Γ and angle θ; Figure 10 Plane P 2 with plane P 3 The schematic diagram of the relationship; Figure 11 Plane P 3 with plane P 4 relationship diagr...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention discloses a cone beam CT system geometric parameter calibration method. The method includes the following steps that projection data of a calibration model at a projection angle is collected; the center line equation of each linear object is determined according to the projection data of the model, the position of the intersection point of center lines is worked out, and then the lengths of the sides of a quadrangle formed by projections of the four linear objects on a detector are worked out; phi is calculated with the ratio of the left side to the right side, theta is calculated with the ratio of the upper side to the lower side, and delta D can be worked out according to the length of any side of the projection quadrangle; eta, delta u and delta v are calculated with phi, theta and the projection coordinates of the intersection point of two adjacent straight lines on a calibration template on a detector plane which includes phi and theta and deviates by delta D in the X axis direction; after the geometric parameters are obtained, FDK reconstruction with the parameters is carried out, and a corrected reconstructed image is obtained. According to the method, improvement is carried out on the basis of a four-point model, the wireframe model is proposed, and the model retains the advantages of the four-point model that 6 geometric parameters are worked out through one time of projection and the calculation amount is small, and improves noise immunity compared with a point model.

Description

technical field [0001] The invention belongs to the technical field of non-destructive testing, and in particular relates to a calibration model and method for correcting geometric parameters of a cone-beam CT system. Background technique [0002] Computed Tomography (CT) technology is an important non-destructive testing technology, which has the advantages of high resolution, high sensitivity and multi-level. The most representative reconstruction algorithm of the cone beam CT system is the FDK reconstruction algorithm, and the FDK algorithm requires that the cone beam CT imaging system must satisfy the ideal imaging geometric relationship, that is, the line connecting the ray source, the center of rotation, and the center of the detector is perpendicular to the detector plane and perpendicular to the axis of rotation of the turntable. However, it is difficult for the actual cone-beam CT system to satisfy this ideal relationship, which will lead to serious artifacts in th...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): A61B6/03
CPCA61B6/032A61B6/583
Inventor 王珏蔡玉芳向前胡传晒葛敏雪
Owner CHONGQING UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com