Abstract: A bar code reader and decoder for reading and decoding linear bar coded information through the use of a logarithmic time base generator. The ratio of the widths of the coding segments are computed for decoding the bar coded data by utilizing a logarithmic time base generator for providing a logarithmic measure of the widths of preselected coding segments and accumulating the logarithmic timing signals in up/down counters to provide a logarithmic representation of the ratios of the widths of the segments. The resultant count of an up/down counter is applied to a translation table to provide a signal representative of equality in widths between compared coding segments or the relative widths in terms of greater than or less than in the direction of scanning.

Abstract: A bar code reader and decoder for reading and decoding linear bar coded information through the use of a logarithmic time base generator. The ratio of the widths of the coding segments are computed for decoding the bar coded data by utilizing a logarithmic time base generator for providing a logarithmic measure of the widths of preselected coding segments and accumulating the logarithmic timing signals in up/down counters to provide a logarithmic representation of the ratios of the widths of the segments. The resultant count of an up/down counter is applied to a translation table to provide a signal representative of equality in widths between compared coding segments or the relative widths in terms of greater than or less than in the direction of scanning.