PURPOSE: To simplify the structure of an electron gun and enable it to be widely applied to various kinds of display devices by controlling the display color of each picture element according to the luminous intensities of a set of three differently-colored phosphors by causing each electron beam discharged from an electron gun to strike a set of three differently-colored phosphors in one horizontal scanning.

CONSTITUTION: On a fluorescent film 5, phosphors R, G and B emitting red, green and blue colors respectively under beam irradiation are formed in three stripes extending in X-direction: the number of each color of phosphors (R, G or B) coincides with the number of scanning beams. In scannings of X-direction (horizontal direction) in which beam 8 pass through mask holes 6R, the phosphors R are irradiated to emit red colors. In the same manner as above, in scannings of X-direction in which beams 8 pass through mask holes 6G and 6B, the phosphors G and B emit green and blue colors. When three times of horizontal scannings carried out by causing an electron beam 8 to strike upon a red, a green and a blue phosphor R, G and B respectively are supposed to be one unit scanning, the display color of each picture element in Y-direction can be varied according to the luminous intensities of a set of three differently-colored phosphors. Thus, the display of one picture element is performed by three times of scannings of one electron beam.