Image forming apparatus, image forming method, and printed matter

摘要

An image forming apparatus forms an image on a recording medium by discharging ink droplets onto the recording medium. The image forming apparatus includes a head having a nozzle orifice that discharges ink droplets onto the recording medium, a main-scanning controller that controls the movement of the head in a main-scanning direction, a main-scanning encoder that generates a position signal indicating the position of the head in the main-scanning direction at a certain interval, a timing generating unit that generates a timing signal with a phase shifted from the position signal, a signal output unit that outputs a recording signal of a waveform pattern corresponding to image data at a timing of the timing signal, and a head drive unit that discharges ink droplets from the nozzle orifice in accordance with the recording signal.

主权项

1. An image forming apparatus that forms an image on a recording medium by discharging ink droplets onto the recording medium, the image forming apparatus comprising:
a head comprising L (L is an integer of 2 or larger) nozzle orifices that discharge ink droplets of different colors onto the recording medium; a main-scanning controller that controls movement of the head in a main-scanning direction; a main-scanning encoder that generates a position signal indicating the position of the head in the main-scanning direction, at a certain interval; a timing generating unit that generates a timing signal with a phase shifted from the position signal; a signal output unit that outputs a recording signal of a waveform pattern corresponding to image data at a timing of the timing signal; a head drive unit that discharges ink droplets from the nozzle orifices in accordance with the recording signal; and a scan controller that controls the main-scanning controller so as to cause the nozzle orifices to perform scans N (N is an integer of 2 or larger) times in the main-scanning direction at the same position in a sub-scanning direction orthogonal to the main-scanning direction, wherein the timing generating unit generates timing signals having different phases for each of the N scans at the same position in the sub-scanning direction, and the scan controller causes, for said each of the N scans, ink droplets of plural different colors to be discharged from the nozzle orifices at the same position in the sub-scanning direction.