摘要:
The invention relates to converter element (100) for a radiation detector, particularly for a Spectral CT scanner. The converter element (100) comprises at least two conversion cells (131) that are at least partially separated from each other by intermediate separation walls (135) which affect the spreading of electrical signals generated by incident radiation (X). The conversion cells (131) may particularly consist of a crystal of CdTe and/or CdZnTe. Said crystal is preferably grown by e.g. vapor deposition between preformed separation walls.
摘要:
The invention relates to a radiation detector (200), particularly an X-ray detector, which comprises at least one sensitive layer (212) for the conversion of incident photons (X) into electrical signals. A two-dimensional array of electrodes (213) is located on the front side of the sensitive layer (212), while its back side carries a counter-electrode (211). The size of the electrodes (213) may vary in radiation direction (y) for adapting the counting workload of the electrodes. Moreover, the position of the electrodes (213) with respect to the radiation direction (y) provides information about the energy of the detected photons (X).
摘要:
The invention relates to a radiation detector (200), particularly an X-ray detector, which comprises at least one sensitive layer (212) for the conversion of incident photons (X) into electrical signals. A two-dimensional array of electrodes (213) is located on the front side of the sensitive layer (212), while its back side carries a counter-electrode (211). The size of the electrodes (213) may vary in radiation direction (y) for adapting the counting workload of the electrodes. Moreover, the position of the electrodes (213) with respect to the radiation direction (y) provides information about the energy of the detected photons (X).
摘要:
A method includes generating enhanced image data based on lower dose image data and a predetermined image quality threshold, wherein an image quality of the enhanced image data is substantially similar to an image quality of higher dose image data, and a system includes an image quality enhancer (128) that generates enhanced image data based on lower dose image data and a predetermined image quality threshold, wherein an image quality of the enhanced image data is substantially similar to an image quality of higher dose image data.
摘要:
A method includes generating a plurality of scatter distributions based on geometric models having different object to detector distances, determining an imaged object to detector distance, and identifying a scatter distribution of the plurality of scatter distributions having a object to detector distance that corresponds to the imaged object to detector distance. The method also includes employing the identified scatter distribution to scatter correct projection data corresponding to the imaged object. Another method includes generating an estimate of wedge scatter by propagating a predetermined wedge scatter profile through an intermediate reconstruction of an object; and employing the estimate to wedge scatter correct the projection data.
摘要:
Method of generating an image of an object by means of an imaging system which has a radiation source that rotates relative to the object about an axis of rotation within a defined rotation angle range, said radiation source projecting radiation onto a radiation detector in order to record projection data, wherein at predefinable relative rotation angle positions of the radiation source a signal which is used to trigger recording of the projection data is generated, and also apparatus for carrying out this method.
摘要:
When generating a 3D image of a subject or patient, a cone beam X-ray source (20a, 20b) is mounted to a rotatable gantry (14) opposite an offset flat panel X-ray detector (22a, 22b). A wedge-shaped attenuation filter (24a, 24b) of suitable material (e.g., aluminum or the like) is adjustably positioned in the cone beam to selectively attenuate the beam as a function of the shape, size, and density of a volume of interest (18) through which X-rays pass in order to maintain X-ray intensity or gain at a relatively constant level within a range of acceptable levels.
摘要:
When generating a 3D image of a subject or patient, a cone beam X-ray source (20a, 20b) is mounted to a rotatable gantry (14) opposite an offset flat panel X-ray detector (22a, 22b). A wedge-shaped attenuation filter (24a, 24b) of suitable material (e.g., aluminum or the like) is adjustably positioned in the cone beam to selectively attenuate the beam as a function of the shape, size, and density of a volume of interest (18) through which X-rays pass in order to maintain X-ray intensity or gain at a relatively constant level within a range of acceptable levels.
摘要:
Adaptively controlling an imaging system (200, 205) includes constructing model feature characteristics (105) of a process over time, determining parameters and commands (110) for controlling the imaging system for each state of the process, performing data acquisition (120) for the process, extracting current features (130) of the process from the acquired data, matching (135) the current features (130) with the model feature characteristics (105) to determine a state of the process (140), and controlling the data acquisition based on the state of the process to produce optimized data.
摘要:
The invention relates to an X-ray detector (1) with an array (2) of sensor elements (21), wherein each row (i) of sensor elements is connected via an addressing line to an addressing unit (5), and wherein each column j) of sensor elements is connected via a read-out line to a read-out unit (3). In the read-out unit (3), sensor signals are preprocessed, for example amplified by amplifiers (31). The detector further comprises a control unit (6) which is adapted to set the gains of said amplifiers (31) for each column (j) and each row (i) individually. The values of the gains may particularly be derived from a priori knowledge, from previous images of the object, or from the image signals of rows that have already been read out.