A CT system and method thereof are disclosed. The system includes: a conveyor mechanism; a first scanning stage configured to scan the object and generate a first digital signal; a second scanning stage spaced from the first scanning stage at a preset distance in a direction of the object's movement; a processing device configured to reconstruct a CT image of the object at a first image quality based on the first digital signal, and analyze the CT image; and a control device configured to adjust a scanning parameter of the second scanning stage based on an analysis result of the processing device to cause the second scanning stage to output a second digital signal. The processing device reconstructs a CT image of the object at a second image quality higher than the first image quality at least based on the second digital signal. The system takes full advantage of the distributed ray sources which replace the normal slip ring technology.

A CT scanning system may include a multi-pixel x-ray source, and a detector array. The multi-pixel x-ray source may have a plurality of pixels that are disposed along a z-axis, and that are sequentially activated so as to controllably emit x-rays in response to incident electrons. The detector array may have one or more rows of x-ray detectors that detect the x-rays that are emitted from the pixels and have traversed an object, and generate data for CT image reconstruction system. In third generation CT scanning systems, the number of detector rows may be reduced. Multi-pixel x-ray source implementation of saddle curve geometry may render a single rotation single organ scan feasible. Using a multi-pixel x-ray source in stationary CT scanning systems may allow x-ray beam design with a minimal coverage to satisfy mathematical requirements for reconstruction.

A calculation method for a dual-energy X-ray imaging system is provided. The calculation method for the dual-energy X-ray imaging system includes the following steps. A plurality of material attenuation coefficient ratio of the dual-energy projection image are established according to the reference materials with known material characteristics. The effective atomic number of each reference material and the material attenuation coefficient ratio are used to establish a calibration data set. A rational polynomial approximation method is adopted to obtain the characteristic model related to the material attenuation coefficient ratio of the reference material and the effective atomic number of the reference material. The material attenuation coefficient ratio of the dual-energy projection image of unknown material is established. The material attenuation coefficient ratio of the unknown material is substitute into the characteristic model to obtain the effective atomic number corresponding to the unknown material.

The present invention provides a CT image calibration method and device and a CT system. The method includes: arranging a fixed calibration element at the outside of a channel area and within the maximal reconstruction area of a CT scanning device, and storing the theoretical value of the fixed calibration element; collecting the projection data of the fixed calibration element to obtain the actual reconstructed image of the fixed calibration element; and comparing the actual reconstructed image with the stored corresponding theoretical value, to establish a mapping function for correcting the actual reconstructed image into the theoretical value. By adopting the present invention, the calibration quality can be effectively improved, the image calibration effect is enhanced, the reliability of the CT scanning device is improved and the maintenance cost is saved, thus the practical application value is very high.

Apparatuses are provided for evaluating an image quality of an image produced by an x-ray computed tomography (CT) system.

The present application discloses a CT system and a detection apparatus for the CT system. The detection apparatus includes: a high-energy detector assembly including a plurality of rows of high-energy detectors arranged along a predetermined trajectory; a low-energy detector assembly including a plurality of rows of low-energy detectors arranged at intervals along the predetermined trajectory, the low-energy detector assembly and the high-energy detector assembly being disposed in a stack; a number of rows of the low-energy detectors is smaller than a number or rows of the high-energy detectors; and each row of the low-energy detectors covers a row of high-energy detectors.

An array (1) for detecting electromagnetic radiation is provided for a radiographic inspection system (20). The array has a plurality of detector elements (2) arranged consecutively along a scan line which extends in a first direction (Y). Each of the detector elements has a detection surface (3) for receiving electromagnetic radiation and converting the received electromagnetic radiation into a corresponding detection signal. Each detection surface (3) has a surface normal (4, N) that extends in a common plane (S) and converges into a common focus (5). The common plane (S) extends in the first direction (Y). The distances between the common focus and the detection surfaces along the respective surface normal (4, N) are different for at least two detector elements.

The present invention relates to image processing devices and related methods. The image processing device (10) comprises a data input (11) for receiving spectral computed tomography volumetric image data organized in voxels. The image data comprises a contrast-enhanced volumetric image of a cardiac region in a subject's body and a baseline volumetric image of that cardiac region, e.g. a virtual non-contrast image, wherein the contrast-enhanced volumetric image conveys anatomical information regarding coronary artery anatomy of the subject. The device comprises a flow simulator (12) for generating, or receiving as input, a three-dimensional coronary tree model based on the volumetric image data and for simulating a coronary flow based on the three-dimensional coronary tree model. The device comprises a perfusion synthesis unit (13) for generating a perfusion image representative of a blood distribution in tissue at at least one instant in time taking at least the baseline volumetric image and said coronary flow simulation into account.

CT scanner comprising a scanning conveyor (9) mounted on a supporting structure and configured to move an object (3) for CT examination forward through a scanning area (8), an input conveyor (10) configured to convey the object until the scanning chamber (2), and an output conveyor (11) configured to convey an object (3) out of the scanning chamber (2), wherein the input conveyor (10), the scanning conveyor (9) and the output conveyor (11) are configured to move forward the object (3) placed on a supporting unit (19) mechanically detached therefore, and wherein the scanning conveyor (9) is configured to rotate the supporting unit (19) and the object (3) on themselves as they travel through the scanning area (8). The input conveyor (10) and the output conveyor (11) are fitted with shields configured in such a way as to intercept all x-rays emitted from the scanning area (8) which escape from the scanning chamber (2) towards the conveyors.

Various embodiments are directed toward systems and methods relating to security screening. For example, a screening system includes chamber scanners oriented to scan different heights corresponding to different respective portions of a user, to identify whether the user is carrying an item that is to be divested. The screening system also includes a divestment scanner configured to obtain a detailed item characterization of the item divested from the user.