1 / 8

Basic Principles of Computed Tomography

Basic Principles of Computed Tomography. Dr. Kazuhiko HAMAMOTO Dept. of Infor. Media Tech. Tokai University. What is the CT?. Mathematical transform to the measured data. Reconstruct n dimension function (image) => projection data of n – 1 dimension

elliotc
Download Presentation

Basic Principles of Computed Tomography

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Basic Principles of Computed Tomography Dr. Kazuhiko HAMAMOTO Dept. of Infor. Media Tech. Tokai University

  2. What is the CT? • Mathematical transform to the measured data. • Reconstruct n dimension function (image) => projection data of n – 1 dimension • Radon Transform (1917)“Two dimension and three dimension object can be reconstructed from the infinite set of projection data”. • The First CT: 1973 in the U.S.4 minutes scan, thickness of 10mm

  3. Concept of CT ・Getting the shape by back projection of the projection data. ・For example, outward view is the quadrangle => it is the cylinder CT Algorithm

  4. X Blur Basic principle of CT-Reconstruction of 2 dimensional image- Projection Data curvilinear integral of absorption coefficient regarding Y y y X-ray detector array Y X x x object X X-ray tube Reconstruction field Data Acquisition field Simple Backprojection

  5. y x X x ω or x Basic principle of CT -Reconstruction of 2 dimensional image- Projection Data x * Filtered Projection data Reconstruction Filter Multidirectional Backprojection Filtered Backprojection

  6. Reconstruction process

  7. Reconstruction process Data acquisition at angle : 0 – 180 degree Obtain F(u,v) and then 2D IFFT -> reconstruction Radon Transform is equivalent to Filtered backprojection !

  8. Example of Simulation Model Image SimpleBackprojection Filtered Backprojection

More Related