A magnetically microfocused electron emission source apparatus is disclosed. The apparatus may include a magnetic emitter unit, wherein the magnetic emitter unit comprises an emitter. Further, the magnetic emitter unit may include one or more magnetic portions formed from one or more magnetic materials, wherein the one or more magnetic portions of the magnetic emitter unit are configured to generate a magnetic field proximate to a tip of the emitter of the magnetic emitter unit for enhancing focusing of the emitted electrons from the electron emitter.

An electron emission source is provided. The electron emission source comprises a first electrode, an insulating layer, and a second electrode, The first electrode, the insulating layer, and the second electrode are successively stacked with each other. the second electrode is a graphene layer, and the graphene layer is an electron emission end to emit electron. A thickness of the graphene layer ranges from about 0.1 nanometers to about 50 nanometers.

A photoinjector system containing modularly-structured waveguide-mode launcher, which is reversibly connected to the RF gun (containing a tubular construction formed with disattachably-affixed to one another structurally-complementary halves); and a solenoid magnet in operation enclosing such tubular structure in a central hollow. The resulting quality, power, and frequency rate of operation as well as cost of manufacturing and operation of the system are superior as compared with those of a related art system.

The present invention addresses the problem of providing a device with which it is possible to adjust the focal point of an electron beam both toward a shorter focal point and toward a longer focal point after an electronic gun was fitted on a counterpart device.

The aforementioned problem can be solved by an electron gun including a photocathode, and an anode, the electron gun furthermore comprising an intermediate electrode disposed between the photocathode and the anode, the intermediate electrode comprising an electron-beam passage hole through which an electron beam released from the photocathode passes, and the electron-beam passage hole having formed therein a drift space in which, when an electrical field is formed between the photocathode and the anode due to application of a voltage, the effect of the electrical field can be disregarded.

A light modulated electron source utilizes a photon-beam source to modulate the emission current of an electron beam emitted from a silicon-based field emitter. The field emitter's cathode includes a protrusion fabricated on a silicon substrate and having an emission tip covered by a coating layer. An extractor generates an electric field that attracts free electrons toward the emission tip for emission as part of the electron beam. The photon-beam source generates a photon beam including photons having an energy greater than the bandgap of silicon, and includes optics that direct the photon beam onto the emission tip, whereby each absorbed photon creates a photo-electron that combines with the free electrons to enhance the electron beam's emission current. A controller modulates the emission current by controlling the intensity of the photon beam applied to the emission tip. A monitor measures the electron beam and provides feedback to the controller.

A field emission cathode device and method for forming a field emission cathode device involve a cathode element having a field emission surface, and a gate electrode element disposed in spaced-apart relation to the field emission surface of the cathode element so as to define a gap therebetween, with the gate electrode element having a plurality of parallel grill members or a mesh structure laterally-extending between opposing anchored ends. A film element laterally co-extends and is engaged with the gate electrode element, with the film element being arranged to allowed electrons emitted from the field emission surface of the cathode element to pass therethrough, and to cooperate with the gate electrode element and the cathode element to form a substantially uniform electric field within the gap and about the field emission surface.

The present disclosure provides a method of manufacturing an electron source. The method includes forming one or more fixed emission sites on at least one needle tip, the fixed emission sites including a reaction product formed by metal atoms on a surface of the needle tip and gas molecules.

The present disclosure provides an electron source, including one or more tips, wherein at least one of the tips comprises one or more fixed emission sites, wherein at least one of the tips includes one or more fixed emission sites, wherein the emission sites includes a reaction product of metal atoms on a surface of the tip with gas molecules.

The present disclosure provides an electron source operating method, the electron source including at least one emission site fixed on a tip, the emission site being a reaction product formed by metal atoms of a surface of the tip and gas molecules under an electric field, and the operating method comprises emitting electrons by controlling operating parameters of the electron source.

An electron gun comprising a cathode having an electron emitting surface and whose planar shape is circular; a heater; an anode being arranged to oppose the cathode; and a heat resistant member. The anode applies a positive potential relative to the cathode to extract electrons in a predetermined direction. The cathode has, in a central portion thereof, a through hole along a central axis of the cathode. The heat resistant member has a first portion to close the through hole and a second portion being positioned between the cathode and the heater.