ELECTRON GUN HAVING COLD CATHODE

摘要

PURPOSE: An electron gun having a cold cathode is provided to reduce a divergent angle of electron by forming a grid having apertures of various shapes and electron emission sources of uniform height. CONSTITUTION: A substrate(61) is formed with a glass or a wafer. A conductive cathode(62) is formed on an upper face of on the substrate(61). An insulating layer(63) is formed on an upper face of the conductive cathode(62). An electron emission source(64) is formed on an upper face of the cathode(62) through a cavity(65). The cavity(65) is formed on a part of the insulating layer(63). The electron emission source(64) has an erect shape. The electron emission source(64) is formed with a carbon nano tube or a graphite or a diamond like carbon. A grid(66) of metal material is formed on an upper face of the insulating layer(63). A multitude of apertures(66a) are formed in the grid(66) to emit electron beam from the electron emission sources(64). The apertures(66a) have various shapes.