A control electrode portion for passing electrons through a given electron-passing hole selected from a plurality of electron-passing holes provided on an insulating substrate is formed by coating the insulating substrate with a conductive film and dividing the into a plurality of conductive films as control electrodes. This structure obviates the mesh structure of electrons which are necessary in the case of arranging control electrodes on the insulating substrate, thereby realizing high-definition display devices with improved luminance. In addition, planar display devices provided with a surface insulated substrate produced by forming an insulating film on a conductive substrate having electron-passing holes and a plurality of separate control electrodes arranged on the surface insulated substrate, it is possible to prevent the charge-up effect which obstructs the passage of electron beams and, hence, to enhance the luminance at least by (1) providing a voltage applying circuit for applying a predetermined voltage to the conductive substrate, (2) providing a portion at which the conductive substrate is exposed between the adjacent control electrodes.