Plane emissive cathode structure of field emission display

In a plane emissive cathode structure of a field emission display having a common plane structure, a cathode plate includes a cathode substrate, and a plurality of cathode units on the cathode substrate, and the cathode unit includes an emitter layer, a gate electrode layer and a dielectric layer. The emitter layer and the gate electrode layer are disposed on a common plane of the cathode substrate and separated with each other to form an interval. The dielectric layer is formed in the interval between the emitter layer and the gate electrode layer, but not connected to the interval between the emitter layer and the gate electrode layer, so as to change the electric field distribution of the emitter layer and the gate electrode layer.