Method and apparatus for registration control during processing of a workpiece particularly during producing images on substrates in preparing printed circuit boards

摘要

A method and apparatus for controlling a processing machine to perform a processing operation on a workpiece by (a) determining the nominal locations of at least two sensible reference marks on the workpiece in terms of the coordinates of the workpiece; (b) loading the workpiece on the processing machine; (c) sensing, and measuring the actual locations of, the reference marks on the workpiece when so mounted, in terms of the coordinates of the processing machine; (d) determining at least one geometrical transformation needed to transform the workpiece coordinates of the nominal locations of the reference marks to the processing machine coordinates of the actual locations of the reference marks; (e) and controlling the processing machine in accordance with the determined geometrical transformation.