摘要:
A distributed X-ray source (3) and an imaging system (1) comprising such an X-ray source (3) are proposed. The X-ray source (3) comprises an electron beam source arrangement (19) and an anode arrangement (17). The electron beam source arrangement (19) is adapted to emit electron beams (24) towards at least two locally distinct focal spots (27) on the anode arrangement (17). Therein, the X-ray source is adapted for displacing the anode arrangement (17) with respect to the electron beam source arrangement (19). While the provision of a plurality of focal spots allows acquisition of projection images under different projection angles thereby allowing reconstruction of three-dimensional X-ray images e.g. in tomosynthesis application, a displacement motion of the anode arrangement (17) with respect to the electron beam source arrangement (19) may allow for distributed heat flux to the anode arrangement thereby possibly reducing cooling requirements.
摘要:
A distributed X-ray source (3) and an imaging system (1) comprising such an X-ray source (3) are proposed. The X-ray source (3) comprises an electron beam source arrangement (19) and an anode arrangement (17). The electron beam source arrangement (19) is adapted to emit electron beams (24) towards at least two locally distinct focal spots (27) on the anode arrangement (17). Therein, the X-ray source is adapted for displacing the anode arrangement (17) with respect to the electron beam source arrangement (19). While the provision of a plurality of focal spots allows acquisition of projection images under different projection angles thereby allowing reconstruction of three-dimensional X-ray images e.g. in tomosynthesis application, a displacement motion of the anode arrangement (17) with respect to the electron beam source arrangement (19) may allow for distributed heat flux to the anode arrangement thereby possibly reducing cooling requirements.
摘要:
This invention relates to high power X-ray sources, in particular to those equipped with a rotating X-ray anode capable of delivering a higher short time peak power than conventional rotating x-ray anodes. This invention can overcome the thermal limitation of peak power by allowing fast rotation of the anode and by introducing a lightweight material with high thermal conductivity in the region adjacent to the focal track material. The fast rotation can be provided by using sections of the rotating anode disk made of anisotropic high specific strength materials with high thermal stability that can be specifically adapted to the high stresses of anode operation. Uses include high speed image acquisition for X-ray imaging, for example, of moving objects in real-time such as in medical radiography.
摘要:
The present invention is related to high power X-ray sources, in particular to those ones that are equipped with rotating X-ray anodes capable of delivering a much higher short time peak power than conventional rotating X-ray anodes according to the prior art. The herewith proposed design principle thereby aims at overcoming thermal limitation of peak power by allowing extremely fast rotation of the anode and by introducing a lightweight material with high thermal conductivity (2) in the region adjacent to the focal track material (4). The extremely fast rotation is enabled by providing sections of the rotary anode disk made of anisotropic high specific strength materials with high thermal stability (1, 3, 6) which will be specifically adapted to the high stresses building up when the anode is operated, as for example fiber-reinforced ceramic materials. An X-ray system equipped with a high peak power anode according to the present invention will be capable of high speed image acquisition with high resolution and high coverage. Such a high-speed rotary anode disk can advantageously be applied in X-ray tubes for material inspection or medical radiography, for X-ray imaging applications which are needed for acquiring image data of moving objects in real-time, such as e.g. in the scope of cardiac CT, or for any other X-ray imaging application that requires high-speed image data acquisition. According to a further exemplary embodiment, the invention is directed to a rotary anode disk divided into distinct anode segments (10a, 10b) with adjacent anode segments which may e.g. be limited to each other by straight radial (14a) or S-shaped slits (14b) ranging from the inner anode bulk (1) to the inner radial edge of the anode disk's outer frame section (3). Other exemplary embodiments of the present invention relate to a rotary anode disk structure design which comprises liquid metal conductors (16a) between the inner anode bulk (1) and a rotary shaft (12) needed for rotating the rotary anode disk about its rotational axis (5), said liquid metal conductors (16a) providing a liquid metal connection between the rotary anode and its rotary shaft (12), or to a rotary anode disk structure which comprises a sliding radial connection (17) and a flexible heat conductor (18) between the inner anode bulk (1) and the rotary shaft (12).
摘要:
For x-ray tubes the focal spot temperature is a critical factor. According to an exemplary embodiment of the present invention, an examination apparatus is provided which has a synchronisation unit providing an operation mode for a stereo tube in which the anode rotation frequency is synchronised with the switching frequency such that the switching frequency is a half integer multiple of the anode rotation frequency. This may lead to a significant reduction of the focal spot temperature.
摘要:
X-ray systems for use in high-resolution imaging applications with an improved power rating are provided. An X-ray source comprises at least one integrated actuator unit (206, 206′, 206a or 206b) for performing at least one translational and/or rotational displacement by moving the position of the X-ray source's anode (204, 204′, 204a′ or 204b′) relative to a stationary reference position. This helps to overcome power limitations due to an overheating of the anode at its focal ̂spot position (205). In addition to that, a focusing unit (203) for allowing an adapted focusing of the anode's focal spot (205) which compensates deviations in the focal spot size resulting from said anode displacements and/or a deflection means (211, 21 Ia or 21 Ib) for generating an electric and/or magnetic field deflecting the electron beam (202, 202a or 202b) in a direction opposite to the direction of the rotary anode's displacement movement may be provided.
摘要:
Systems and methods for data acquisition in computed tomography (CT) applications are provided. The systems and methods are particularly adapted for scanning and acquiring/processing data in connection with high-power cone-beam CT applications. The electron beam is moved/scanned along the anode surface to multiple focal positions. Data acquisition for a full projection at one focus position and one view angle is achieved by activating each focus position multiple times during the data acquisition for one angle of the gantry. The detector array and associated data processing system are adapted to rapidly switch between the different focus positions during the acquisitions for one view angle and to collect all data belonging to the same projection into the same data set. Adaptive electron optics are utilized to move/scan the electron beam along the anode surface to the various focus positions. Alternatively, a plurality of cathodes may be provided for respective focus positions and the system may support fast switching therebetween to achieve desirably short spot times. The disclosed CT system permits greater power densities without risk of heat damage to the anode and effectively increases the track velocity of the electron beam on the anode surface. The CT system and associated data acquisition methods have particular utility in CT applications requiring increased time resolution and/or spatial resolution, e.g., cardiac CT applications.
摘要:
The rotating anode x-ray tube comprises an anode, whose focal track has the shape of a saddle trajectory. A proper anode angle to enable a high power line focus is always realised along the focal path on the anode. The x-ray tube is for CT scanners and enables a movement of the focal spot along the patient axis during gantry rotation. In this way, cone beam artefacts due to the reconstruction may be avoided.
摘要:
Systems and methods for data acquisition in computed tomography (CT) applications are provided. The systems and methods are particularly adapted for scanning and acquiring/processing data in connection with high-power cone-beam CT applications. The electron beam is moved/scanned along the anode surface to multiple focal positions. Data acquisition for a full projection at one focus position and one view angle is achieved by activating each focus position multiple times during the data acquisition for one angle of the gantry. The detector array and associated data processing system are adapted to rapidly switch between the different focus positions during the acquisitions for one view angle and to collect all data belonging to the same projection into the same data set. Adaptive electron optics are utilized to move/scan the electron beam along the anode surface to the various focus positions. Alternatively, a plurality of cathodes may be provided for respective focus positions and the system may support fast switching therebetween to achieve desirably short spot times. The disclosed CT system permits greater power densities without risk of heat damage to the anode and effectively increases the track velocity of the electron beam on the anode surface. The CT system and associated data acquisition methods have particular utility in CT applications requiring increased time resolution and/or spatial resolution, e.g., cardiac CT applications.
摘要:
The device improved according to the invention comprises a micro-electromechanical switch (MEMS) with a piezoelectric element connected to a mechanical support on both sides at the edges. The electrode design of this piezoelectric element is characterized by two electrodes mounted on at least one of the surfaces.