Dispenser Cathode - Multi-Beam Electron Gun
Original Publication Date: 1988-Jan-01
Included in the Prior Art Database: 2005-Feb-14
A technique is described whereby the brightness of a multi-beam electron gun is increased through the use of a tungsten dispenser cathode along with an array of grids, which are precisely formed in the substrate above it. The resulting high electron output provides increased brightness, of the multi-beam electron gun, without grid heat causing grid emission. The technique uses laser and photo etching technologies to construct the grid structure and either mask or string techniques are used with an electro discharge machine to cut the flat dispenser blocks into the required shapes for the cathode. Before the cathode is impregnated, it is cut to produce mesas for electron sources and pins for mechanical clamping of the grid, as shown in the figure.