Method for Inspecting Lead Pin Insertion Into Card Through-Holes
Original Publication Date: 1987-Jul-01
Included in the Prior Art Database: 2005-Feb-01
Cards are inspected to check whether lead pins of components have been properly inserted into through-holes of the cards. After assembly of the components, the backside of the card is scanned by a video camera and its image is digitized. The digital image of each through-hole area is then analyzed by spiral scan starting from the center of the through-hole. If a lead pin is properly inserted, the spiral scan will find a white pel region before reaching a preset end point. The spiral scan is efficient to analyze the digital image for detection of a lead pin inserted into the through-hole. Fig. 1 illustrates images for two states: a correct state (Fig. 1A), where the through-hole 10 has a lead pin 20 properly inserted therein and an incorrect state (Fig.