A cathode of an electron emitting device is described, where the cathode comprises a carbon nanotube (CNT); a nano-filler material; and a carbonizable polymer, and where the cathode exhibits increased hardness, is formed by high temperature thermal treatment, and is devoid of a substrate. Also described is a method of forming a cathode of an electron emitting device, where the method comprises a) forming a dispersed mixture comprising a carbon nanotube, a nano-filler material, and a carbonizable polymer in a solvent; b) coating and/or extruding the mixture; c) drying the coated and/or extruded mixture to remove at least a substantial portion of the solvent; and d) subjecting the dried mixture to a high temperature thermal treatment; where the method results in the cathode of an electron emitting device having increased hardness.

Provided is an infrared optical sensor including a substrate, a channel layer on the substrate, optical absorption structures dispersed and disposed on the channel layer, and electrodes disposed on the substrate, and disposed on both sides of the channel layer, wherein the channel layer and the optical absorption structures include transition metal dichalcogenides.

The present invention is directed to a method for the fabrication of electron field emitter devices, including carbon nanotube (CNT) field emission devices. The method of the present invention involves depositing one or more electrically conductive thin-film layers onto an electrically conductive substrate and performing lithography and etching on these thin film layers to pattern them into the desired shapes. The top-most layer may be of a material type that acts as a catalyst for the growth of single- or multiple-walled carbon nanotubes (CNTs). Subsequently, the substrate is etched to form a high-aspect ratio post or pillar structure onto which the previously patterned thin film layers are positioned. Carbon nanotubes may be grown on the catalyst material layer. The present invention also described methods by which the individual field emission devices may be singulated into individual die from a substrate.

An electron beam source is provided that includes a vessel forming a chamber, a cathode disposed within the chamber, the cathode comprising a low dimensional electrically conductive material having an anisotropic restricted thermal conductivity, an electrode disposed in the chamber, the electrode being connectable to a power source for applying a positive voltage to the electrode relative to the cathode for accelerating free electrons away from the cathode to form an electron beam when the cathode is illuminated by electromagnetic (EM) radiation such that the cathode thermionically emits free electrons, and an electron emission window in the chamber for passing a generated electron beam out of the chamber. An electron microscope that incorporates the electron beam source is also provided.

A field emission assembly and an electromagnetic wave generator are provided, the field emission assembly includes a linear emitter which includes carbon nanotube (CNT) fibers and emits electrons and a holder configured to fix the emitter, both ends of the emitter are fixed to the holder, and the emitter includes at least one of a curved portion so as to form a peak in an electron emission direction and a bent portion so as to form a peak in the electron emission direction.

An emitter, a field emission assembly, and an electromagnetic wave generator are provided, and the emitter is an emitter for emitting electrons in an electromagnetic wave generator and is in the form of a sheet in which a plurality of yarns including carbon nanotube (CNT) fibers are weaved.

The present invention relates to large area field emission devices based on the incorporation of macroscopic, microscopic, and nanoscopic field enhancement features and a designed forced current sharing matrix layer to enable a stable high-current density long-life field emission device. The present invention pertains to a wide range of field emission sources and is not limited to a specific field emission technology. The invention is described as an X-ray electron source but can be applied to any application requiring a high current density electron source.

An X-ray tube has a housing enclosing a vacuum chamber. There is a primary field-emission cathode within the vacuum chamber, a secondary cathode within the vacuum chamber, spaced apart from the primary cathode, and an anode target within the vacuum chamber.

The present disclosure provides a method of manufacturing a carbon nanotube electron emitter, including: forming a carbon nanotube film; performing densification by dipping the carbon nanotube film in a solvent; cutting an area of the carbon nanotube film into a pointed shape or a line shape; and fixing the cutting area of the carbon nanotube film arranged between at least two metal members to face upwards with lateral pressure.

The present disclosure relates to an X-ray source apparatus and a control method of the X-ray source apparatus in which a cathode electrode and a gate electrode are arranged in an array form to enable matrix control, and, thus, it is possible to irradiate X-rays at an optimum dose for each position on the subject. Therefore, it is possible to suppress the irradiation of more X-rays than are needed to the subject. Also, it is possible to obtain a high-resolution and high-quality X-ray image. As such, two-dimensional matrix control makes it easy to control the dose of X-rays and makes it possible to uniformly irradiate X-rays to the subject. Therefore, it is possible to manufacture a high-resolution surface X-ray source with less dependence on the size of the focus of electron beams.