Patent · US Expired

METHOD OF AND SYSTEM FOR SCANNING BAR CODE SYMBOLS USING A LASER SCANNING PATTERN HAVING MULTIPLE FOCAL ZONES, WHEREIN THE MINIMUM BEAM DIMENSION/MINIMUM BAR WIDTH (MBD/MBW) RATIO IS GREATER THAN OR EQUAL TO 2.0

US6581835B1 · kind B1 · utility

5Cited by
25References
6Claims
0Family size

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Key dates

Filing dateFeb 9, 2000
Grant dateJun 24, 2003
Priority date
Expiry dateFeb 9, 2020

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06K2207/1013
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A multi-focal zone laser scanning system for scanning bar code symbols having a minimum bar element width (MBW). The multi-focal zone laser scanning system comprises a laser beam producing device for producing a laser beam, and a laser beam scanning mechanism for scanning the laser beam so as to generate a laser scanning pattern having a plurality of different focal zones. In the system, the scanned laser beam has a minimum beam dimension (MBD) with each focal zone, and the ratio of the minimum beam dimension (MDB) within each focal zone to the minimum bar element width (MBW) of a scanned bar code symbol therewithin (i.e. MDB/MBW) is greater than or equal to 2.0. Consequently, less modulation of the laser scanning beam is required during scanning operations, and therefore, bar code symbols having narrower minimum bar element widths can be resolved.

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