Method of inspecting component placement accuracy for each first

Abstract

An improved method for inspecting assembled circuit boards utilizes an existing programmable placement machine having an associated downward looking camera, illumination source, and monitor. After assembling a first circuit board of a series with electrical components according to a program which is particular to that series, and prior to removing the assembled board from the machine, an inspection is performed by: (i) automatically repositioning the relative position of the camera and the assembled circuit board, according to a portion of that same particular program, in order to address each placement position in turn; (ii) automatically acquiring an image of each placement position when it is addressed, and furnishing the image to the monitor in order to provide a magnified image on the monitor screen; (iii) visually inspecting the magnified image on the monitor screen in order to ascertain the presence or absence of the component at each placement position, the deviation in X, Y, and .theta. of the component relative to the desired placement position and/or the accuracy of connection of component leads to their respective lands on the circuit board; and (iv) providing for human control of the time expended at each placement position during the inspecting and correcting the program with any ascertained deviation.