The invention relates to an electron source comprising a conductive substrate, a conductor disposed facing the substrate, the electron source emitting an electron beam when the conductor is positively biased with respect to the substrate, and an electrically insulating crystal arranged on the substrate, facing the conductor, the substrate defining with the crystal a void including at least one peak located at a distance from the crystal, the crystal having, in a plane parallel to the substrate, dimensions of less than 100 nm and a thickness of less than 50 nm.

A power supply circuit and a field emission electron source are provided. The power supply circuit includes: field effect transistors S.sub.i coupled in series via drains and sources in sequence, wherein 1≤i≤n, n≥2, and wherein a source of S.sub.1 is coupled to a negative electrode of a voltage source, and a drain of S.sub.n is used as an output terminal of the power supply circuit to couple to a load; a first group of diodes D.sub.1i coupled in series; a first group of resistors R.sub.1j, 2≤j≤n; and a current feedback module configured to adjust an internal resistance of the field effect transistors S.sub.i, coupled in series in sequence, so as to cause a current passing through the load to be constant; wherein the field effect transistors S.sub.i, 1≤i≤n, operate in a constant current region.

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.

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.

An electron emission device includes a substrate and an electron emission layer. The electron emission layer is provided above the substrate, and is provided with an opening. The electron emission layer has an edge defining the opening and is configured to emit electrons from the edge when the edge is irradiated with light.

Accelerator apparatus (100) for accelerating charged particles (2) with pulsed radiation includes horn-shaped coupling device (10) with at least one horn coupler (11, 15) having input aperture (12), electrically conductive walls (13) and output aperture (14), wherein pulsed radiation is received at input aperture and focused towards output aperture, and waveguide device (20) coupled with the output aperture and configured for receiving focused pulsed radiation. Waveguide device includes injection section (21) for providing charged particles and subjecting them to acceleration by pulsed radiation in injection section, and lateral output port (23) for releasing accelerated charged particles along particle acceleration direction. The at least one horn coupler receives linearly polarized single cycle pulses (1) including broadband frequency spectrum shaped as a linearly polarized plane wave and focuses linearly polarized single cycle pulses. Waveguide device has non-resonant broadband transmission characteristic. Furthermore, charged particle gun and method of accelerating charged particles are described.

Provided is a field emission device including a cathode electrode and an anode electrode, which are spaced apart from each other, an emitter disposed on the cathode electrode, a gate electrode disposed between the cathode electrode and the anode electrode and including a gate opening that overlaps the emitter, and a plurality of alignment electrodes disposed between the gate electrode and the cathode electrode. Here, the alignment electrodes surround a side surface of the emitter.

[Object] To provide an electron source that is lightweight, simple in configuration, and capable of suppressing characteristic degradation or recovering characteristics without causing an increase in power consumption.

[Solving Means] A CNT electron source includes: a CNT emitter 32 for emitting electrons; a gate electrode 33 for extracting electrons from the CNT emitter 32; and a gate power supply connection switching relay 37a and a CNT emitter grounding switching relay 37b that cause the gate electrode 33 to emit electrons to irradiate the CNT emitter with electrons.

The present disclosure provides a thruster device. The device includes a force-generating element mounted to a housing. The element is configured to generate a thrust force for propelling the housing. The element including a first electrode connected to a first input terminal of a power source. A second electrode is spaced apart by a predetermined distance from the first electrode and connected to a second input terminal of the power source. The second electrode includes a second longitudinal axis oriented parallelly to a first longitudinal axis. A dielectric medium is disposed between the electrodes. Upon receiving field emission condition, charged particles available at the first electrode accelerate towards the second electrode for generating a thrust force along a direction of movement of the charged particles. The thrust force is generated when the predetermined distance between the electrodes is shorter than a Rindler horizon defined by the charged particles during acceleration.