A vacuum fluorescent printer including a print head (60) having luminous blocks (32, 33, 34) each having a plurality of luminous elements arranged in a main scanning direction for irradiating a photosensitive material with light released from phosphorous objects to which electrons are applied based on a drive signal, thereby forming dots on the photosensitive material. A further luminous block (32b) is provided which is spaced from the luminous blocks (32a, 33, 34) in the sub-scanning direction and used for printing a particular color among the three colors (R, G, B) Each dot of the particular color is formed by light from a plurality of luminous blocks (32a, 32b). A printer controller (7c) is provided for generating a pulsed drive signal as the drive signal. The number of pulses in the drive signal is determined based on a density value of the image data, and the slower a moving speed is in the sub-scanning direction, to the larger pulse width the drive signal is set.