Patent ID: 6095417
Filing Date: 2000-08-01
Classification: G06K

Abstract:
An apparatus for reading bar codes on a moving web, comprising:a light source arranged on one side of the web for transmitting a beam of light through said web, said beam of light having a plurality of characteristic transmitted intensity levels corresponding to optical density variations in said moving web;a photoelectric scanning means arranged on a side of said web opposite said light source for detecting said beam of light transmitted through said web, said photoelectric scanning means generating an analog output signal proportional to each one of said plurality of characteristic transmitted intensity levels of said beam of light;a converter means for converting said analog output signal to digital data;means for discriminating between light intensity changes associated with variations in said optical density of said web to light intensity changes associated with artifacts in said web, said means comprising a time delay operably associated with said processing means for delaying changes of said output analog signal of said processing means; and,means for processing said digital data, said means producing an analog output signal that manipulates the intensity level of said beam of light produced by said light source to within a predetermined limit.