METHOD OF CALIBRATING A DISPENSER

A method is used to identify and compensate for errors created by changes in the relative positions of a deposition unit and a vision system of a dispenser. The method includes calibrating the vision system, dispensing a pattern of features over a working area, moving the vision system over a deposition location to locate a deposition, obtaining an image of the deposition, tagging data associated with the image, calculating a relative distance between the deposition unit and the vision system, storing correction data with spatial location in a file for later use, and using the stored data to make small corrections prior to dispensing additional material.