A device for applying a constant magnetic field to a volume of interest (VOI) has been developed. At least one magnetic field source and a permeable yoke, which guides the magnetic flux generated by this magnetic field source into the volume of interest (VOI). The yoke is guided through at least one closed conductor loop, which can be switched to the superconducting state so that, in the superconducting state of the conductor loop, a change in the flux through the yoke effects a current counteracting this change along the conductor loop. It has been identified that, in this way, the stabilizer for the magnetic field can be spaced so far apart from the volume of interest (VOI) that the field distribution in this volume is virtually no longer influenced. At the same time, the quality of the stabilization is also improved, since the conductor loop is no longer exposed to the entire magnetic field prevailing in the volume of interest (VOI). The entire critical current that the conductor loop can carry is available as a control range for compensating for fluctuations in the flux. In comparison with the prior art, the invention first accepts the apparent disadvantage that, in general, additional means are required for switching the conductor loop back and forth between the superconducting state and the normal-conducting state. However, this disadvantage is more than compensated for.

Disclosed are methods and devices suitable for producing an electron beam.

The invention relates to a particle beam system (PBS) comprising a particle guiding tube, one or more transversely movable electrodes (of a defined type) providing a transverse electric and/or magnetic field (pulse or linear) wherein a particle flow can be influenced by the electrodes which can further have a defined shape. The PBS can be provided with a protective film and/or an insulation, it can form a mono and/or stereo particle path. The PBC can provide a cross-sectionally shaped beam, an adjustable optical axis, a rotating electric and/or magnetic field, a circularly polarized beam. The PBS can form an array, it can comprise one or more connections, one or more modules. The PBC can be coupled with electro- and/or mechanocomponents. The PBC can form lenses configured in a separate eye ray configuration. A method for providing a particle beam and a digitizer of photographic or X-ray images are proposed.

Example compact modular electron beam units are provided that can be used to generate electron beams using field emitter elements. A modular electron beam unit may comprise an electron beam source including a base portion, at least one field emitter element coupled to the base portion, the field emitter element including a field emitter tip, at least one gate electrode and a membrane window disposed over the at least one gate electrode.

The present invention generally relates to systems and methods for generating controllable beam of electrons using a hollow-cathode triode electron gun that substantially mitigate impact of back-streaming electrons. In one embodiment, a triode hollow-cathode electron gun is configured to provide electrons and substantially mitigates the impact of back-streaming electrons. The triode hollow-cathode electron gun includes a hollow cathode, a heating filament, an anode, a control grid, a shadow grid and a sleeve mechanically coupled to the hollow-cathode. The sleeve is substantially centered on the axis of the triode hollow-cathode electron gun and configured to maintain shape and trajectory of emitted beams of electrons.

The present invention generally relates to systems and methods for generating controllable beam of electrons using a hollow-cathode triode electron gun that substantially mitigate impact of back-streaming electrons. In one embodiment, a triode hollow-cathode electron gun is configured to provide electrons and substantially mitigates the impact of back-streaming electrons. The triode hollow-cathode electron gun includes a hollow cathode, a heating filament, an anode, a control grid, a shadow grid and a sleeve mechanically coupled to the hollow-cathode. The sleeve is substantially centered on the axis of the triode hollow-cathode electron gun and configured to maintain shape and trajectory of emitted beams of electrons.

The method is for automatic astigmatism correction of a lens system. A first image is provided that is not in focus at a first stigmator setting of a set of lenses. A calculating device calculates a corresponding first Fourier spectrum image. A distribution and direction of pixels of the Fourier spectrum image are determined by calculating a first vector and a second vector. The first vector is compared with the second vector. The lens system is changed from a first stigmator setting to a second stigmator setting to provide a second image. A corresponding Fourier spectrum image is calculated. The distribution and direction of pixels of the second Fourier spectrum image is determined by calculating a third vector and a fourth vector. The third vector is compared to the fourth vector. The image that has the lowest vector ratio is selected.

A device for applying a constant magnetic field to a volume of interest (VOI) has been developed. At least one magnetic field source and a permeable yoke, which guides the magnetic flux generated by this magnetic field source into the volume of interest (VOI). The yoke is guided through at least one closed conductor loop, which can be switched to the superconducting state so that, in the superconducting state of the conductor loop, a change in the flux through the yoke effects a current counteracting this change along the conductor loop. It has been identified that, in this way, the stabilizer for the magnetic field can be spaced so far apart from the volume of interest (VOI) that the field distribution in this volume is virtually no longer influenced. At the same time, the quality of the stabilization is also improved, since the conductor loop is no longer exposed to the entire magnetic field prevailing in the volume of interest (VOI). The entire critical current that the conductor loop can carry is available as a control range for compensating for fluctuations in the flux. In comparison with the prior art, the invention first accepts the apparent disadvantage that, in general, additional means are required for switching the conductor loop back and forth between the superconducting state and the normal-conducting state. However, this disadvantage is more than compensated for.

A device for applying a constant magnetic field to a volume of interest (VOI) has been developed. At least one magnetic field source and a permeable yoke, which guides the magnetic flux generated by this magnetic field source into the volume of interest (VOI). The yoke is guided through at least one closed conductor loop, which can be switched to the superconducting state so that, in the superconducting state of the conductor loop, a change in the flux through the yoke effects a current counteracting this change along the conductor loop. It has been identified that, in this way, the stabilizer for the magnetic field can be spaced so far apart from the volume of interest (VOI) that the field distribution in this volume is virtually no longer influenced. At the same time, the quality of the stabilization is also improved, since the conductor loop is no longer exposed to the entire magnetic field prevailing in the volume of interest (VOI). The entire critical current that the conductor loop can carry is available as a control range for compensating for fluctuations in the flux. In comparison with the prior art, the invention first accepts the apparent disadvantage that, in general, additional means are required for switching the conductor loop back and forth between the superconducting state and the normal-conducting state. However, this disadvantage is more than compensated for.