Abstract:
The invention relates to a cathode arrangement comprising: a thermionic cathode comprising an emission portion provided with an emission surface for emitting electrons, and a reservoir for holding a material, wherein the material, when heated, releases work function lowering particles that diffuse towards the emission portion and emanate at the emission surface at a first evaporation rate; a focusing electrode comprising a focusing surface for focusing the electrons emitted from the emission surface of the cathode; and an adjustable heat source configured for keeping the focusing surface at a temperature at which accumulation of work function lowering particles on the focusing surface is prevented.
Abstract:
The invention relates to a cathode arrangement comprising: a cathode body housing an emission surface for emitting electrons in a longitudinal direction, wherein the emission surface is bounded by an emission perimeter; a focusing electrode at least partially enclosing the cathode body in a transversal direction and comprising an electron transmission aperture for focusing the electrons emitted by the emission surface, wherein the aperture is bounded by an aperture perimeter, wherein the cathode body is moveably arranged within the focusing electrode over a maximum transversal distance from an aligned position, and wherein the aperture perimeter transversally extends over the emission surface and beyond the emission perimeter over an overlap distance that exceeds the maximum transversal distance.
Abstract:
An electron gun, having an electron source, a Wehnelt electrode, and acceleration electrodes, includes a control device for changing a field distribution formed by a first acceleration electrode of the acceleration electrodes to control characteristics of a final cross-over formed, by electrons from a first cross-over, at the final stage of the electric gun. The first cross-over is performed when the electrons emitted from the electron source are focused by the field distribution formed by the electron source, the Wehnelt electrode, and a second acceleration electrode of the acceleration electrodes.
Abstract:
A field emission electron source includes: a field emission array portion composed of an insulation layer with a plurality of apertures, which is formed on a substrate, an extraction electrode formed on the insulation layer, and a plurality of cathodes formed respectively on the substrate in the plurality of apertures; a cathode base for fixing the field emission array portion; and an electron lens portion composed of a plurality of electrode members having a function of accelerating and converging an electron beam emitted from the field emission array portion. An emission axis of the electron beam emitted from the field emission array portion has a predetermined angle with respect to an optical axis of the electron lens portion. Thus, the field emission array portion can be protected from impact caused by ions generated in the electron lens portion, thereby improving the life of a field emission electron source.
Abstract:
To provide an electron gun that can improve the focus characteristics of a cathode ray tube by reducing the working area of the cathode, a cathode ray tube equipped with this electron gun that has favorable focus characteristics, and an image display device comprising this cathode ray tube that can achieve favorable images. An area on the electron emission surface of the cathode K that meets the beam hole (11A) of the first grid (11) forms an electron gun in closest proximity to the first grid (11). Provide a cathode ray tube equipped with this electron gun and further provide an image display device formed by this cathode raytube.
Abstract:
Electron guns are disclosed that produce low-brightness and high-emittance electron beams that are suitable for use in an electron-beam reduction-lithography apparatus. A preferred embodiment comprises a cathode, a Wehnelt electrode, an anode, and at least one control electrode placed between the cathode and the anode. Each of these components defines a spherical surface all having a common center point and all thus being concentric with one another. During operation, the anode has a grounded electrical potential while the cathode and the Wehnelt electrode each have a potential of about -100 KV. If the applied voltage to the control electrode is adjusted within a range of -99 to -90 KV, the brightness can be controlled to within a range of 1.times.10.sup.3 to 2.times.10.sup.4 A/cm.sup.2.sr.
Abstract:
A virtual remote cathode has the position of a space charge cloud associated with it fixed by the geometry of a fixed insulating plate. The plate can be made to accurate dimensions and hence the cathode to control grid dimension can be accurately controlled and will not change as a result of any mechanical, electrical or physical changes in the construction. The fixed insulating plate is located on a surface of the control grid facing the cathode.
Abstract:
A system for controlling the shape of a charged particle beam. The particle beam is emitted from a source (58) of the said particles. Said source is associated with a collecting electrode which collects the particles. The system comprises at least one resistive zone (56) and at least two control electrodes (52, 54). The resistive zone and the control electrodes are arranged substantially at the same level as the source. The control electrodes are also placed on either side of the resistive zone and serve to polarize the latter. The electrical resistance profile of the resistive zone is chosen in such a way that it has the potential distribution so that it is possible to obtain the desired shape of the beam from the source when the control electrodes are appropriately polarized.