Patent Document ID: 4823394
Application ID: 06855760
Patent Status: 1

Claim One:
1. A pattern recognition system for determining the position of a candidate die mounted on flexible die holding means comprising: (a) a light source for illuminating the candidate die; (b) means for presenting the candidate die such that the flexible die holding means surrounding said die is inclined at an angle greater than about zero degrees with respect to the plane of the candidate die; (c) means for sensing substantially only that light reflected at an angle of about 90.degree. from the candidate die to provide a video image, whereby the image of the candidate die is enhanced with respect to the image of the die holding means; (d) means for generating digital data representing said video image; (e) memory means for storing said digital data in binary format; (f) means for defining a corridor across said die in said digital data, said corridor having a width y and a length x; (g) means for processing said digital data to obtain a signature element, said signature element being the widthwise summation of said y binary data within said corridor at a plurality of x points along the length of said corridor; and (h) means for analyzing said signature element to distinguish the surface of the candidate die from the surface of the holding means, whereby the position of said candidate die is determined within said corridor.