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 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 invention addresses the problem of providing an electron beam generator and an electron beam applicator for which maintenance is facilitated. The electron beam generator comprises a vacuum chamber, a photocathode holder, an activation vessel, and an internal motive power transmission member. The photocathode holder is capable of moving relative to the activation vessel.

A method of operating a charged particle gun is described. The method includes providing an emitter at a first emitter potential within the charged particle gun and providing a trapping electrode at a first electrode potential within the charged particle gun, wherein the first emitter potential and the first electrode potential is provided to have an electrical field of essentially zero at the emitter and at the trapping electrode; switching the trapping electrode from the first electrode potential to a second electrode potential different from the first electrode potential to generate an electrostatic trapping field at the trapping electrode; and after switching the trapping electrode from the first electrode potential to the second electrode potential, switching on an electrostatic emission field at the emitter.

A high-brightness electron beam source is disclosed. The electron beam source may include a broadband illumination source configured to generate broadband illumination. A tunable spectral filter may be configured to filter the broadband illumination to provide filtered illumination having an excitation spectrum. The electron beam source may further include a photocathode configured to emit one or more electron beams in response to the filtered illumination, wherein emission from the photocathode is adjustable based on the excitation spectrum of the filtered illumination from the tunable spectral filter.

The present invention relates to a handheld material analyser comprising an air-tight chamber having an analysis aperture; an electron beam generation system adapted to direct a beam of electrons through the analysis aperture; an Energy-Dispersive X-ray (EDX) spectroscopy system having a detector located in the chamber; the chamber being adapted to operate at internal pressures between atmospheric pressure and a vacuum of the order of 1 Pa; and a gas inlet adapted to receive an inert gas for generating a plasma in the region of the photocathode. In this way, the plasma can clean the photocathode.

A method of producing an electron emitting device includes: step A of providing an aluminum substrate or providing an aluminum layer supported by a substrate; step B of anodizing a surface of the aluminum substrate or a surface of the aluminum layer to form a porous alumina layer having a plurality of pores; step C of applying Ag nanoparticles in the plurality of pores to allow the Ag nanoparticles to be supported in the plurality of pores; step D of, after step C, applying a dielectric layer-forming solution onto substantially the entire surface of the aluminum substrate or the aluminum layer, the dielectric layer-forming solution containing, in an amount of not less than 7 mass % but less than 20 mass %, a polymerization product having siloxane bonds; step E of, after step D, at least reducing a solvent contained in the dielectric layer-forming solution to form the dielectric layer; and step F of forming an electrode on the dielectric layer.

An emitter (3) and a target (7) are arranged so as to face each other in a vacuum chamber (1), and a guard electrode (5) is provided at an outer circumferential side of an electron generating portion (31) of the emitter (3). The emitter (3) is supported movably in both end directions of the vacuum chamber (1) by the emitter supporting unit (4) having a movable body (40). The emitter supporting unit (4) is operated by an operating unit (6) connected to the emitter supporting unit (4). By operating the emitter supporting unit (4) by the operating unit (6), a distance between the electron generating portion (31) of the emitter (3) and the target (7) is changed, and a position of the emitter (3) is fixed at an arbitrary distance, then field emission is performed with the position of the emitter (3) fixed.