STEREO VISION MEASUREMENT SYSTEM AND METHOD

摘要

A method for automatic, stereo vision based, in-line solder ball height and substrate coplanarity inspection includes providing an imaging setup together with an imaging processor for reliable, in-line solder ball height measurement. The imaging set up includes a pair of cameras mounted at two opposing angles with ring lighting around each camera lens, which allows the capture of two images of an electronics package in parallel. The lighting generates features on solder balls located on a substrate of the electronics package, which are then used to determine height. Specifically, points with the same intensity on each solder ball surface are grouped, which allows for the formation of curves, also known as iso-contours, which are then matched between the two views. An optimized triangulation is then performed to determine the height of each one of the solder balls.

主权项

1. A method of operating an imaging processor in an image processing system comprising:
obtaining at least one stereo image from an imaging setup in the image processing system, wherein the at least one stereo image includes a left view and a right view of an electronics package including a substrate and a plurality of solder balls on a surface of the substrate such that each one of the left view and the right view are obtained from separate cameras located at opposite angles with respect to the electronics package; and for each one of the left view and the right view, grouping a number of points on a surface of each one of the plurality of solder balls together based on the intensity of light reflected from the particular point and connecting the grouped points together in order to form a plurality of iso-contours.