An apparatus includes: a structure having a lumen for accommodating a beam, wherein the structure is a component of a medical radiation machine having a target for interaction with the beam to generate radiation; and a first beam position monitor comprising a first electrode and a second electrode, the first electrode being mounted to a first side of the structure, the second electrode being mounted to a second side of the structure, the second side being opposite from the first side; wherein the first beam position monitor is located upstream with respect to the target.

A field emission device is configured as a heat engine, wherein the configuration of the heat engine is variable.

A field emission device is configured as a heat engine, wherein the configuration of the heat engine is variable.

An image intensifier sensor for acquiring, amplifying and displaying images and including a vacuum envelope, the image intensifier sensor including a photocathode arranged for releasing photoelectrons into the vacuum envelope upon electromagnetic radiation acquired from the images which impinges the photocathode, an anode, spaced apart from and in facing relationship with the photocathode, arranged for receiving the photoelectrons and converting the photoelectrons for displaying the images on the basis thereof, and a power supply unit for providing power to the image intensifier sensor, wherein the image intensifier sensor further includes potting material, wherein the potting material comprises a foam compound.

This electron emitting element includes a lower electrode, a surface electrode facing the lower electrode, a resistance layer arranged between the lower electrode and the surface electrode, and an insulating layer arranged between the lower electrode and the surface electrode. The resistance layer is an insulating resin layer containing conductive fine particles in a dispersed state. The insulating layer has a peripheral region for defining the electron emission region, and an emission control region which is arranged so as to overlap the electron emission region defined by the peripheral region. The emission control region is configured by a line-shaped insulating layer, a plurality of dot-shaped insulating layers, or both a line-shaped insulating layer and a plurality of dot-shaped insulating layers. The percentage of an area that the emission control region represents within an area of an electron emission region defined by the peripheral region is 2% or more and 60% or less.

An apparatus for generating electron radiation comprises: an elongated, wire-shaped hot cathode to emit electron radiation having an elongated, line-shaped cross section perpendicular to a direction of propagation of the electron radiation; a cathode electrode; an anode electrode with an opening through which the electron radiation emitted from the hot cathode can pass, wherein a voltage applied between the cathode electrode and the anode electrode accelerates electrons emitted from the hot cathode; and a deflecting unit to deflect the electron radiation downstream of the opening of the anode electrode, wherein a cross section of the electron radiation perpendicular to the direction of propagation is changed by the deflecting unit to decease a longitudinal extent of the electron radiation and to increase a transverse extent of the electron radiation such that longitudinal and transverse extents of the electron radiation perpendicular to the direction of propagation are about the same size.

An apparatus for generating electron radiation comprises: an elongated, wire-shaped hot cathode to emit electron radiation having an elongated, line-shaped cross section perpendicular to a direction of propagation of the electron radiation; a cathode electrode; an anode electrode with an opening through which the electron radiation emitted from the hot cathode can pass, wherein a voltage applied between the cathode electrode and the anode electrode accelerates electrons emitted from the hot cathode; and a deflecting unit to deflect the electron radiation downstream of the opening of the anode electrode, wherein a cross section of the electron radiation perpendicular to the direction of propagation is changed by the deflecting unit to decease a longitudinal extent of the electron radiation and to increase a transverse extent of the electron radiation such that longitudinal and transverse extents of the electron radiation perpendicular to the direction of propagation are about the same size.

An apparatus for generating electron radiation comprises: an elongated, wire-shaped hot cathode to emit electron radiation having an elongated, line-shaped cross section perpendicular to a direction of propagation of the electron radiation; a cathode electrode; an anode electrode with an opening through which the electron radiation emitted from the hot cathode can pass, wherein a voltage applied between the cathode electrode and the anode electrode accelerates electrons emitted from the hot cathode; and a deflecting unit to deflect the electron radiation downstream of the opening of the anode electrode, wherein a cross section of the electron radiation perpendicular to the direction of propagation is changed by the deflecting unit to decease a longitudinal extent of the electron radiation and to increase a transverse extent of the electron radiation such that longitudinal and transverse extents of the electron radiation perpendicular to the direction of propagation are about the same size.

An apparatus includes: a structure having a lumen for accommodating a beam (e.g., electron beam, proton beam, or a charged particle beam), wherein the structure is a component of a medical radiation machine having a target for interaction with the beam to generate radiation; and a first beam position monitor comprising a first electrode and a second electrode, the first electrode being mounted to a first side of the structure, the second electrode being mounted to a second side of the structure, the second side being opposite from the first side; wherein the first beam position monitor is located upstream with respect to the target.

An apparatus includes: a structure having a lumen for accommodating a beam (e.g., electron beam, proton beam, or a charged particle beam), wherein the structure is a component of a medical radiation machine having a target for interaction with the beam to generate radiation; and a first beam position monitor comprising a first electrode and a second electrode, the first electrode being mounted to a first side of the structure, the second electrode being mounted to a second side of the structure, the second side being opposite from the first side; wherein the first beam position monitor is located upstream with respect to the target.