Patent ID: 9184016
Filing Date: 2015-11-10
Classification: H01J

Abstract:
1. A field emission cathode device, comprising: a cathode electrode having a planar surface; an electron emitter located on the planar surface of the cathode electrode and electrically connected to the cathode electrode, wherein the electron emitter comprises a plurality of sub-electron emitters, a height of the electron emitter gradually reduces from a center of the electron emitter out to each of edge of the electron emitter; and a connecting line of the end of each of the plurality of sub-electron emitters, away from the cathode electrode, is consistent with the shape of the sidewall of the through-hole; an electron extracting electrode spaced from the cathode electrode by a dielectric layer, wherein the electron extracting electrode defines a through-hole, and a part of the plurality of sub-electron emitters extends to the through-hole; wherein the distances between an end of each of the plurality of sub-electron emitters away from the cathode electrode and the closest portion of a sidewall of the through-hole are substantially equal.