Patent ID: 7309118

Claim:
A method for measuring an x-stitch error in a marking device having a plurality of printheads, the method comprising: printing a test pattern with at least two of the plurality of printheads, each printhead printing a plurality of dashes in the test pattern; sensing the test pattern across the at least two printheads using a linear array sensor; determining positions of the plurality of dashes printed with each printhead; and determining an x-stitch error based on the determined positions of the plurality of dashes, wherein the x-stitch error represents a displacement of a printhead in a cross process direction from its optimal spacing, the cross process direction being perpendicular to a process direction in which a print medium advances; sensing the test pattern comprises obtaining, across the plurality of printheads, a profile of linear array sensor responses to the plurality of dashes; determining positions of the plurality of dashes comprises determining a dash center x-position for each dash based on minimum response locations in the linear array sensor response profile, the dash center x-position being a cross process direction location of a center of a dash; and determining the dash center x-position comprises using quadratic interpolation to obtain the dash center x-position.