A video image display apparatus of the flat tube and multi line cathode type of the present invention includes a phosphor screen, and a predetermined number (e.g. 15) of line cathodes for in-turn emitting a predetermined number of horizontal rows of electron beams. Each row has a second predetermined number (e.g. 320) of rod shaped electron beams for together producing one horizontal line of image on the phosphor screen. A vertical deflection means is provided for vertical deflection of the electron beams in turn at one vertically divided segment corresponding to one of the horizontal rows by means of a vertical deflection signal, e.g. a step wave having a saw-tooth wave envelope. The envelope is adjusted so as to be expanded or compressed or level changed, thereby eliminating any undesirable black horizontal band on the screen due to non-uniformity of electrode construction. A uniform raster is thereby obtainable.