Abstract:
A field emission device includes a cathode and a carbon nanotube (CNT) gate electrode. The CNT gate electrode which is electrically insulated from the cathode includes a CNT layer and a dielectric layer. The CNT layer which has a surface includes a number of micropores. The dielectric layer is coated on the surface of the CNT layer and an inner wall of each of the micropores.
Abstract:
An apparatus for X-ray imaging includes a cylindrical X-ray generator assembly including linear X-ray generators arranged along a circumference of a cylinder and having a linear shape, a linear X-ray detector disposed inside the cylindrical X-ray generator assembly, and a rotation driver rotating the linear X-ray detector along an inner circumference of the cylindrical X-ray generator assembly.
Abstract:
A method for making field emission electron source comprises following steps. An insulating layer is coated on outer surface of a linear carbon nanotube structure. A field emission electron source preform is formed by locating a plurality of conductive ring on outer surface of the insulating layer, wherein the plurality of conductive ring is space from each other, and each conductive ring comprises a first ring face and a second ring face opposite to the first ring face. A plurality of field emission electron source is formed by cutting off the plurality of conductive ring, the insulating layer, and the linear carbon nanotube structure, wherein each field emission electron source comprises at least one conductive ring, and a ring face of the conductive ring, end surface of the insulating layer, and end surface of the linear carbon nanotube structure are coplanar.
Abstract:
A field emission cathode device includes a cathode substrate, a gate electrode, a first dielectric layer, a cathode electrode, and an electron emission layer. The gate electrode is located on a surface of the cathode substrate. The first dielectric layer is located on a surface of the gate electrode and defines a first opening to expose part of the gate electrode. The cathode electrode is spaced from the gate electrode through the first dielectric layer defining a second opening in alignment with the first opening. A field emission display using the field emission cathode device is also related.
Abstract:
The invention relates to a pumped electron source (1) that includes an ionization chamber (4), an acceleration chamber (2) with an electrode (3) for extracting and accelerating primary ions and forming a secondary-electron beam, characterized in that the pumped electron source (1) includes a power supply (11) adapted for applying to the electrode (3) a positive voltage for urging a primary plasma (17) outside the acceleration chamber (2), and a negative voltage pulse for extracting and accelerating the primary ions and forming a secondary-electron beam.
Abstract:
A device includes an anode, a cathode, and a grid configured to modulate a flow of electrons from the cathode to anode. The grid is made of graphene material which is substantially transparent to the flow of electrons.
Abstract:
A field emission device includes a cathode and a carbon nanotube (CNT) gate electrode. The CNT gate electrode which is electrically insulated from the cathode includes a CNT layer and a dielectric layer. The CNT layer which has a surface includes a number of micropores. The dielectric layer is coated on the surface of the CNT layer and an inner wall of each of the micropores.
Abstract:
An electron beam apparatus is provided having an electron emitting device which has a simple configuration, exhibits high electron emission efficiency, operates stably, and in which emitted electrons are effectively converged. The electron beam apparatus includes: an insulator having a notch on its surface; a gate positioned on the surface of the insulator; at least one cathode having a protruding portion protruding from an edge of the notch toward the gate, and positioned on the surface of the insulator so that the protruding portion is opposed to the gate; and an anode arranged to be opposed to the protruding portion via the gate, wherein the gate is formed on the surface of the insulator so that at least a part of a region opposed to the cathode is projected outward and recessed portions are provided in which ends of the gate are recessed and interpose the projected region.
Abstract:
The present invention relates to a field emission apparatus and a method of driving the field emission apparatus, which has a three-pole structure of dual emitters formed on both first and second electrodes of a rear substrate in order to obviate a distinction between a gate and a cathode, thus enabling dual field emission. In such a field emission apparatus, a ground is formed between an anode and a point of the first and second electrodes of the rear substrate, and a square wave is applied thereto in order to alternately generate field emission in the first and second electrodes, thus increasing a light-emitting area and emission efficiency, decreasing a driving voltage and consumption power, saving the manufacturing cost and manufacturing time, and accomplishing a longer lifespan.