Abstract: A slip ring assembly includes a base body, at least one first conductor, and at least one second conductor. The base body is configured to have an annular shape and adapted to be made of an insulating material, and the base body includes a first side and a second side opposite to the first side along an axial direction of the base body. The first conductor is configured to have an annular shape and adapted to be fixed on the first side or the second side. The second conductor is configured to have an annular shape and adapted to be fixed on the first side or the second side. The first conductor and the second conductor are electrically insulated, and a projection of the first conductor and a projection of the second conductor along the axial direction of the base body at least partially overlap.

Abstract: According to an aspect of the present disclosure, a beam control device for radiotherapy is provided. The beam control device may include an electron beam generator configured to emit an electron beam for radiotherapy toward a subject in a first direction. The beam control device may further include a first deflection device configured to generate a defocused electron beam by defocusing the electron beam in a second direction, the second direction being different from the first direction.

Abstract: A slip ring assembly includes: at least one first conductor group, and at least one second conductor group. Each first conductor group includes a first conductor and a second conductor, and the first conductor and the second conductor are configured as annular shapes, respectively. Each second conductor group includes a third conductor and a fourth conductor, the third conductor and the fourth conductor are configured as annular shapes, respectively. The first conductor, the second conductor, the third conductor and the fourth conductor are arranged to be apart from each other. A first current having a first phase and a first amplitude is configured to flow through the first conductor, a second current having a second phase and a second amplitude is configured to flow through the second conductor, a third current having a third phase and a third amplitude is configured to flow through the third conductor.

Abstract: The present disclosure provides a treatment system including a radiotherapy device, a magnetic resonance imaging (MRI) device, and a support. The radiotherapy device is configured to emit a radiation beam. The MRI device may include a magnet assembly for providing a magnet field in an accommodation space. The support may be configured to be connected with the radiotherapy device, and the radiotherapy device may be configured to rotate around at least one rotation axis.

Abstract: Embodiments of the present disclosure provide a radiotherapy system, comprising a first imaging component, a second imaging component, and a treatment component. The first imaging component and second imaging component may be used to determine a target region of an object and/or to guide an emission of treatment rays. The treatment component may be used to emit the treatment rays toward the target region. An isocenter of the treatment component may coincide with an isocenter of the second imaging component.

Abstract: The present disclosure is related to a microwave source. The microwave source may include a cathode heater and a thermionic emitter. The cathode heater may include a first component, and a second component enclosing at least a portion of the first component. The thermionic emitter may be configured to release electrons when the thermionic emitter is heated by the cathode heater. At least a portion of the second component of the cathode heater may be in contact with the thermionic emitter.

Abstract: A method for calibrating a medical device is provided. The medical device may include a magnetic resonance (MR) device. The method may include switching a gradient field in at least one gradient direction of the MR device; obtaining a magnetic flux variation in the at least one gradient direction in at least one portion of a spatial region within a gradient field domain of the MR device using a magnetic flux measurement component; determining a center of the gradient field domain of the MR device based on the magnetic flux variation; and performing a mechanical adjustment on the MR device to locate the center of the gradient field domain at a target position based on the center of the gradient field domain, or adjusting an image reconstruction process to correct or eliminate an impact of inaccuracy of the center of the gradient field domain on a reconstructed image.

Abstract: Embodiments of the present disclosure disclose an examination room shield, comprising: a peripherally closed shield side wall, and a sub-shield assembly disposed in an inner space enclosed by the shield side wall, the sub-shield assembly including a peripherally closed sub-shield side wall.

Abstract: The present disclosure is related to a microwave source. The microwave source may include a cathode heater and a thermionic emitter. The cathode heater may include a first component, and a second component enclosing at least a portion of the first component. The thermionic emitter may be configured to release electrons when the thermionic emitter is heated by the cathode heater. At least a portion of the second component of the cathode heater may be in contact with the thermionic emitter.

Abstract: A method may include identifying a time window of a procedure. The method may also include obtaining operational information of the time window. The operational information may include a limit of pulse repetition frequency (PRF) acceleration and a plurality of preliminary radio frequency (RF) PRFs. The method may also include determining a plurality of updated RF PRFs by updating the plurality of preliminary RF PRFs. A rate of variation between any two adjacent updated RF PRFs may be less than or equal to the limit of PRF acceleration. The method may also include causing an RF source to generate electromagnetic waves at the plurality of updated RF PRFs in the time window.

Abstract: A method may include identifying a time window of a procedure. The method may also include obtaining operational information of the time window. The operational information may include a limit of pulse repetition frequency (PRF) acceleration and a plurality of preliminary radio frequency (RF) PRFs. The method may also include determining a plurality of updated RF PRFs by updating the plurality of preliminary RF PRFs. A rate of variation between any two adjacent updated RF PRFs may be less than or equal to the limit of PRF acceleration. The method may also include causing an RF source to generate electromagnetic waves at the plurality of updated RF PRFs in the time window.

Abstract: The present disclosure provides a magnetic resonance imaging (MRI) device. The MRI device may include a main magnet configured to generate a main magnetic field. The main magnet may form an accommodation space configured to accommodate a target object. The main magnet may include at least one group of main field coils. A direction of the main magnetic field generated by the at least one group of main field coils may form a preset angle with an axial direction of the accommodation space. The at least one group of main field coils may include a first group of main field coils and a second group of main field coils that are arranged oppositely along a radial direction of the accommodation space. Each of the first group of main field coils and the second group of main field coils may bend towards each other.

Abstract: A method for quality assurance may include obtaining a state of a medical device. The method may also include obtaining a target plan of a target subject. The method may also include determining a prediction result based on the state of the medical device and the target plan of the target subject. The method may also include determining whether a quality assurance test passes based on the prediction result.

Abstract: The embodiments of the present disclosure provide a radiation therapy device. The radiation therapy device may comprise a beam generating device, a scanning magnet, and one or more focusing magnets. The beam generating device may be configured to generate a charged particle beam. The scanning magnet may be configured to diverge the charged particle beam. The one or more focusing magnets may be configured to deflect the charged particle beam diverged by the scanning magnet.

Abstract: The present disclosure provides a device and an equipment for radiation ray generation. The device may include: a radiation target assembly configured to generate radiation rays under irradiation of an electron beam with a predetermined energy; and a heat dissipation assembly arranged on a back surface of the radiation target assembly, wherein a range of a thickness of the target assembly may be determined based on a peak of energy deposition of a target material of the radiation target assembly under the irradiation of the electron beam with the predetermined energy.

Abstract: The present disclosure is related to a microwave source. The microwave source may include a cathode heater and a thermionic emitter. The cathode heater may include a first component, and a second component enclosing at least a portion of the first component. The thermionic emitter may be configured to release electrons when the thermionic emitter is heated by the cathode heater. At least a portion of the second component of the cathode heater may be in contact with the thermionic emitter.

Abstract: According to an aspect of the present disclosure, a beam control device for radiotherapy is provided. The beam control device may include an electron beam generator configured to emit an electron beam for radiotherapy toward a subject in a first direction. The beam control device may further include a first deflection device configured to generate a defocused electron beam by defocusing the electron beam in a second direction, the second direction being different from the first direction.

Abstract: A method may include identifying a time window of a procedure. The method may also include obtaining operational information of the time window. The operational information may include a limit of pulse repetition frequency (PRF) acceleration and a plurality of preliminary radio frequency (RF) PRFs. The method may also include determining a plurality of updated RF PRFs by updating the plurality of preliminary RF PRFs. A rate of variation between any two adjacent updated RF PRFs may be less than or equal to the limit of PRF acceleration. The method may also include causing an RF source to generate electromagnetic waves at the plurality of updated RF PRFs in the time window.