Electron emission with electron emission regions on cathode electrodes

An electron emission device includes components for inhibiting the diffusion of electron beams, decreasing the light emission of incorrect colors, and preventing the diode type electron emission due to the anode electric field. In particular, the electron emission device includes a substrate with grooves, and electron emission regions filling the grooves. Cathode electrodes are provided at the substrate such that the cathode electrodes are electrically connected to the electron emission regions. Gate electrodes are formed over the cathode electrodes while interposing an insulating layer.