Patent ID: 6236747
Filing Date: 2001-05-22
Classification: G01N,G06T,H05K

Abstract:
A method of inspecting a ball and bumped grid array to highlight desired features while masking unwanted features, said method comprising the steps of:a. sequentially illuminating said ball and bumped grid array using first and second illumination apparatuses, said first and second illumination apparatuses selected to illuminate said unwanted features similarly and to illuminate said desired features differently;b. capturing a first image of said ball and bumped grid array with an image capture device while said array is illuminated with said first illumination apparatus;c. capturing a second image of said ball and bumped grid array with said image capture device while said array is illuminated with said second illumination apparatus; andd. processing said first and second images by subtracting second image from said first image to produce a resulting image wherein said unwanted features are eliminated.