Method of Imaging a Coding Pattern With Data Elements Encoding by Pulse-Position Modulation

摘要

A method of imaging a coding pattern disposed on a surface of a substrate. The method comprises the steps of: (a) capturing an image of a portion of the coding pattern; and (b) low-pass filtering the captured image so as to obscure data elements in the image and preserve target elements in the image. The data elements encode data values by pulse position modulation, which facilitates the low-pass filtering.