Tomography principles and current applications

Terahertz &quot;T-ray&quot; tomography

Figure 1 - (a) A projection line is defined by an angle ...

Figure 2 - (a) Acquisition of several distinct angles; (b) Intersection of the data available on the different projections enables f to be reconstructed more accurately.

Figure 3 - (a) Analytical Shepp-Logan ghost represented in an image ...

Figure 4 - Zoom on Shepp-Logan ghost reconstructions

Figure 6 - X-ray scan of a patient&#039;s rib cage. The anatomical structure is clearly visible: spinal bones and ribs (white), fatty tissue (light grey) and lungs (dark grey).

Figure 11 - Some parameters for building THz imaging contrast

Figure 12 - a) Reference time measurement and spectrum transmitted by silica; b) Reference time measurement and spectrum transmitted by sapphire

Figure 13 - (a) Experimental setup (mm beam path in green); (b) Example of sample to be investigated: Terakenstein

Figure 14 - (a) 2D projections acquired between 0 and 180...

Figure 15 - Object composed of four metal rods (two 10 mm diameter rods in the background and on the left, a 12 mm diameter rod on the right and an 8 mm diameter rod in the foreground).

Figure 16 - Sinograms of four metal bars (2 of ...

Figure 17 - Sections of the four metal bars obtained from the sinogram in figure 16(b)

Figure 18 - Horizontal intensity profiles along the line passing through the center of the top metal bar (obtained from images in figure 17)

Figure 19 - Image reconstruction of the Terakenstein sample at position cut y &#61; 25 using sinograms with 9, 12, 18, and 36 projections and the BFP, SART and OSEM methods.

Figure 20 - SSIM as a function of the number of projections and the reconstruction method

Figure 22 - Reconstructions of the Terakenstein object

Figure 24 - Comparison of horizontal intensity profiles of a metal bar obtained with SART and optimized SART

Figure 25 - 3D visualization of Terakenstein reconstructions by BFP, SART and optimized OSEM