The conventional attenuation contrast imaging does not yield satisfactory sensitivity and specificity for weakly absorbing media, such as biological soft tissues. The x-ray scattering offer an important contrast mechanism to reveal structural features and density fluctuation within an object. This scattering signal carries information at the molecular and supra-molecular level, and has a tremen...

Radar imaging and x-ray computed tomography (CT) are both based on inverting the Radon transform. Yet radar imaging can make images from as little as two degrees of aperture while x-ray CT typically requires an aperture of at least 120◦. Our discussion addresses this phenomenon. (Some figures in this article are in colour only in the electronic version)

Themathematical principles of computed tomography (CT) were first investigated by J. Radon [28] as early as 1917 and were later extended to complex fields by Kirillov [22]. The first application of tomography was, surprisingly, in radio astronomy [2], and today, it finds usage in diverse fields such as medical imaging, seismology, and underwater acoustic imaging. In medical imaging, CT has had ...

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X-ray computed tomography (CT) systems with high resolution (also known as micro-CT systems) have been developed over the last two decades and have been used with great success in small animal studies. A micro-CT scanner is based on the same underlying physical principle as a clinical CT scanner, but it is designed for higher-resolution imaging. It produces three-dimensional (3D) tomographic da...

Most existing X-ray computed tomography (CT) techniques work in single-mounted mode and need to scan the inspected objects one by one. It is time-consuming and not acceptable for the inspection in a large scale. In this paper, we report a multi-mounted CT method and its first engineering implementation. It consists of a multi-mounted scanning geometry and the corresponding algebraic iterative r...

We study the 3D reconstruction of a binary scene from X-ray tomographic data. In the special case of a compact and uniform object lying in a uniform background, the scene is entirely defined by the object surface. Then, we select parametric surface models, and we directly estimate their parameters from the data. After showing the ability of spherical harmonics and first order splines (polyhedra...

background and aims. cone-beam computed tomography (cbct) is an imaging system which has many advantages over computed tomography (ct). in ct scan, hounsfield unit (hu) is proportional to the degree of x-ray attenuation by the tissue. in cbct, the degree of x-ray attenuation is shown by gray scale (voxel value). the aim of the present study was to investigate the relationship between gray scale...

We discuss standard X-ray-imaging techniques. Phase-imaging methods and a new class of nano-focus and nanoresolution laboratory systems offer new opportunities in true laboratory-based X-ray microtomography with a host of possible applications that have mainly been demonstrated only at synchrotron sources. Notwithstanding these advances, the diffraction limit for X-ray-imaging methods is a long...

BACKGROUND In computed tomography (CT), the source-detector system commonly rotates around the object in a circular trajectory. Such a trajectory does not allow to exploit a detector fully when scanning elongated objects. OBJECTIVE Increase the spatial resolution of the reconstructed image by optimal zooming during scanning. METHODS A new approach is proposed, in which the full width of the...