PURPOSE: To facilitate the positioning of electrodes, to prevent the impairment of an ion layer even when openings are made small and provided densely, and to achieve high speed, by making slits in either the upper or lower electrode, with an insulated layer for the control of an ion flow therebetween, and in the insulated layer, and by using the other as an opening electrode.

CONSTITUTION: When a DC voltage is applied between the corona wire 14 and the casing electrode 15, corona ions are produced, and they are guided to an ion control part 21 by means of an electric field produced between the corona wire 14 and the upper electrode 18. Slits are made in the electrode 18 of the control part 21 and an insulated layer 17, and the guided ions pass through the slits to be further guided to the lower opening electrode 20. Therefore, a latent image is formed on an electrostatic recording drum 17 by the control of the application of voltages to the upper slit electrodes 18a...18f and the lower opening electrodes 20a...20g, 20a'...20g' according to image signals and by the ON/OFF control of an ion flow in a unit recording element in the form of a matrix. Even when the array pitches and openings of the electrodes are made small, a decrease in an amount of ions can be prevented by the slits through which produced ions are effectively introduced.