Patent · US Expired

Method and apparatus for magnetic ink character recognition using a magneto-resistive read head

US5729621A · kind A · utility

12Cited by
10References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 31, 1995
Grant dateMar 17, 1998
Priority date
Expiry dateAug 31, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06K7/084
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A signal extraction and character recognition system is provided for an MICR system using E13B font characters and a magneto-resistive read head. Each character is treated as defining a block comprising a matrix of equal sized zones. Because adjacent characters are separated by space (e.g., non-residually magnetized regions), the read head output signal is used to first identify the start of each character. As the document bearing the characters moves relative to the head, the signal strength from each vertical zone is summed. The relative vertical column signal strength is then compared to the vertical column signal strength for the preceding column to form a ratio set. The ratios are then quantized into one of three levels, depending upon whether R>T.sub.1 (a first threshold, preferably 4/3), R<T.sub.2 (a second threshold, preferably 3/4), T.sub.2 .ltoreq.R.ltoreq.T.sub.1. The patterns of these three quantized levels uniquely identify the 14 characters in the E13B character set. These patterns from the processed output signal from the magneto-resistive head are compared with the contents of a look-up table (or the equivalent) containing patterns for the 14 characters in the E13B …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.