Patent · US Expired

Code reading apparatus

US4859840A · kind A · utility

22Cited by
2References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 16, 1988
Grant dateAug 22, 1989
Priority date
Expiry dateJun 16, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06K7/0166
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A code reading apparatus of a bar code reader which has detecting means for outputting a reading signal responsive to the code displayed on a medium, edge detecting means for detecting the edge of the reading signal, counting means for starting counting each edge detected by the edge detecting means. Discriminating means outputs a reset signal to decoding means when the counted value started for counting by the counting means is a product or more of the quotient produced by dividing the allowable maximum width of the code by the allowable minimum width and the counted value counted between the edges immediately before by the counting means, when the quotient produced by dividing the counted value started for counting by the counting means by the counted value counted between the edges immediately before is a quotient or more produced by dividing the allowable maximum width of the code by the allowable minimum width. Thus, the apparatus can discriminate the start even if the starting margin before the code of the bar code is short.

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