Imaging Components, Systems, and Processing

View-dependent geometric calibration for offset flat-panel cone beam computed tomography systems

[+] Author Affiliations
Van-Giang Nguyen

Le Quy Don Technical University, Department of Information Systems, 236 Hoang Quoc Viet, Bac Tu Liem, Ha Noi, Vietnam

Opt. Eng. 55(4), 043102 (Apr 12, 2016). doi:10.1117/1.OE.55.4.043102
History: Received December 5, 2015; Accepted March 15, 2016
Text Size: A A A

Abstract.  Geometric parameters that define the geometry of imaging systems are crucial for image reconstruction and image quality in x-ray computed tomography (CT). The problem of determining geometric parameters for an offset flat-panel cone beam CT (CBCT) system, a recently introduced modality with a large field of view, with the assumption of an unstable mechanism and geometric parameters that vary in each view, is considered. To accurately and rapidly find the geometric parameters for each projection view, we use the projection matrix method and design a dedicated phantom that is partially visible in all projection views. The phantom consists of balls distributed symmetrically in a cylinder to ensure the inclusion of the phantom in all views, and a large portion of the phantom is covered in the projection image. To efficiently use calibrated geometric information in the reconstruction process and get rid of approximation errors, instead of decomposing the projection matrix into actual geometric parameters that are manually corrected before being used in reconstruction, as in conventional methods, we directly use the projection matrix and its pseudo-inverse in projection and backprojection operations of reconstruction algorithms. The experiments illustrate the efficacy of the proposed method with a real offset flat-panel CBCT system in dental imaging.

Figures in this Article
© 2016 Society of Photo-Optical Instrumentation Engineers

Citation

Van-Giang Nguyen
"View-dependent geometric calibration for offset flat-panel cone beam computed tomography systems", Opt. Eng. 55(4), 043102 (Apr 12, 2016). ; http://dx.doi.org/10.1117/1.OE.55.4.043102


Access This Article
Sign in or Create a personal account to Buy this article ($20 for members, $25 for non-members).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging & repositioning the boxes below.

Related Book Chapters

Topic Collections

Advertisement


 

  • Don't have an account?
  • Subscribe to the SPIE Digital Library
  • Create a FREE account to sign up for Digital Library content alerts and gain access to institutional subscriptions remotely.
Access This Article
Sign in or Create a personal account to Buy this article ($20 for members, $25 for non-members).
Access This Proceeding
Sign in or Create a personal account to Buy this article ($15 for members, $18 for non-members).
Access This Chapter

Access to SPIE eBooks is limited to subscribing institutions and is not available as part of a personal subscription. Print or electronic versions of individual SPIE books may be purchased via SPIE.org.