A method of sheet registration and a sheet stacker with a sheet registration device

To compensate for sheet registration errors and to produce a desired target sheet offset between upstream and downstream positions of a sheet path along which sheets travel successively in a predetermined sheet travel direction, each sheet is driven along the path in at least three successive phases, i.e. a first phase in which the sheet is driven differentially to rotate the sheet in a first direction, a second phase in which the sheet s driven uniformly in the sheet travel direction, and a third phase in which the sheet is driven differentially with a driving velocity versus time profile opposite to that in the first phase, to rotate the sheet in a second direction opposite the first direction. If the sheet has a skew error, an intermediate phase in which the sheet is driven differentially with a driving velocity versus time profile dertmined to correct for the detected skew error, is nested in the second phase.