Patent ID: 8807690

Claim:
A method of forming a test pattern in a printer, wherein the printer comprises at least one liquid discharge head comprising a nozzle plate, and the nozzle plate has a plurality of nozzles formed therethrough, wherein the plurality of nozzles are configured to discharge a liquid and are arranged in a plurality of rows which are parallel to each other and extend in a particular direction perpendicular to a conveying direction of a medium, the plurality of nozzles are arranged in a plurality of discharge-nozzle areas arranged in the particular direction, such that the plurality of discharge-nozzle areas cover an entire conveying area of the medium in the particular direction, the method comprising the steps of: selecting only a first nozzle of the plurality of nozzles from a first row of the plurality of rows; selecting only a second nozzle of the plurality of nozzles from a second row of the plurality of rows; discharging the liquid from the first nozzle onto the medium to form a first line comprising a plurality of liquid droplets and extending in the conveying direction and from the second nozzle onto the medium to form a second line comprising a plurality of liquid droplets and extending in the conveying direction immediately adjacent to the first line, wherein a third row of the plurality of rows is positioned between the first row and the second row in the conveying direction, wherein the nozzles arranged in each of the plurality of rows extending in the particular direction are spaced at a constant interval; determining whether a position of the at least one discharge head corresponds to a desired predetermined position based on a position of the liquid discharged from the first nozzle onto the medium and a position of the liquid discharged from the second nozzle onto the medium, wherein the first row is positioned furthest from the second row among the plurality of rows in the conveying direction; selecting a third nozzle of the plurality of nozzles from the third row immediately adjacent to the first nozzle in the particular direction; selecting a fourth nozzle of the plurality of nozzles from a fourth row of the plurality of rows immediately adjacent to the second nozzle in the particular direction; and discharging the liquid from the third nozzle and from the fourth nozzle onto the medium, wherein a particular line intersects at least a portion of the first nozzle, at least a portion of the second nozzle, at least a portion of the third nozzle, and at least a portion of the fourth nozzle, and the fourth row is positioned between the first row and the second row.