A Stationary CT Scheme Based on Field Emission Flat-panel X-ray Source Array

Haitao Cheng, Kai Wang, Xuanqin Mou


Published in:Fully3D 2017 Proceedings


field emission cathode, flat-panel x-ray sources, iterative reconstruction
With the development of field emission x-ray cold cathodes of nanomaterials, several new x-ray imaging geometries have been proposed. Compared with thermionic x-ray tube, this new type of x-ray tube is of great advantages, such as fast response, low energy consumption and individually addressable switching. In this work, a new tomographic geometry is devised, in which a stationary polygon-shape flat-panel cathode source array is employed to avoid mechanical movement for scanning. With an array of sources implemented in a flat-panel, each source irradiates a narrow cone beam x-ray and all the beams from the panel are overlapped to cover the scanned object. A number of the flat-panels, as well as x-ray detectors of the same number, are grouped as a polygon that encloses the object to implement a rotation-free projection acquisition. With the proposed geometry, we experimentally explore two scanning schemes, i.e., switching source separately or simultaneously. Numerical experiments demonstrated that in separating switching, low root mean square error and high contrast to noise ratio is achieved with more sources distributed in the flat-panel. For simultaneous switching, image quality is restricted by few-view nature and overlapping projection. With the limitation of constant current power and x-ray dose, the scheme of 10×10 sources distributed in the flat-panel can produce an advisable reconstruction result.
Haitao Cheng
Institute of Image Processing and Pattern Recognition, Xi'an Jiaotong University, China
Kai Wang
Institute of Image Processing and Pattern Recognition, Xi'an Jiaotong University, China
Xuanqin Mou
Institute of Image Processing and Pattern Recognition, Xi'an Jiaotong University, China
  1. Li Y, Sun Y, Yeow J T W. Nanotube field electron emission: principles,development, and applications[J]. Nanotechnology, 2015, 26(24):242001.
  2. Baughman R H, Zakhidov A A, de Heer W A. Carbon nanotubes--the route toward applications[J]. science, 2002, 297(5582): 787-792.
  3. Zhang J, Yang G, Cheng Y, et al. Stationary scanning x-ray source based on carbon nanotube field emitters[J]. Applied Physics Letters, 2005,86(18): 184104.
  4. Zhang J, Cheng Y, Lee Y Z, et al. A nanotube-based field emission x-ray source for microcomputed tomography[J]. Review of scientific instruments, 2005, 76(9): 094301.
  5. Yang G, Rajaram R, Cao G, et al. Stationary digital breast tomosynthesis system with a multi-beam field emission x-ray source array[C]. Medical Imaging. International Society for Optics and Photonics, 2008:69131A-69131A-10.
  6. Quan E M, Lalush D S. Three-dimensional imaging properties of rotation-free square and hexagonal micro-CT systems[J]. IEEE transactions on medical imaging, 2010, 29(3): 916-923.
  7. Zhang Z, Yu S, Liang X, et al. A novel design of ultrafast micro-CT system based on carbon nanotube: A feasibility study in phantom[J].Physica Medica, 2016, 32(10): 1302-1307.
  8. Chen D, Song X, Zhang Z, et al. Transmission type flat-panel X-ray source using ZnO nanowire field emitters[J]. Applied Physics Letters,2015, 107(24): 243105.
  9. Sidky E Y, Kao C M, Pan X. Accurate image reconstruction from few-views and limited-angle data in divergent-beam CT[J]. Journal of X-ray Science and Technology, 2006, 14(2): 119-139.
  10. Segars W P, Tsui B M W, Frey E C, et al. Development of a 4-D digital mouse phantom for molecular imaging research[J]. Molecular Imaging & Biology, 2004, 6(3): 149-159.
  11. Kim D, Ramani S, Fessler J A. Accelerating X-ray CT ordered subsets image reconstruction with Nesterov’s first-order methods[C]. Proc. Intl. Mtg. on Fully 3D Image Recon. in Rad. and Nuc. Med. 2013: 22-5.
  12. Wang G, Jiang M. Ordered-subset simultaneous algebraic reconstruction techniques (OS-SART)[J]. Journal of X-ray Science and Technology, 2004,12(3):169-177.