Method and apparatus for the reading of a bar code
US6145745A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 21, 1998 |
| Grant date | Nov 14, 2000 |
| Priority date | — |
| Expiry date | Apr 21, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K7/14
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method is described for the reading of a bar code consisting of a predetermined number of code elements for the production of a binary signal with sequential high and low phases the length of which correspond to the width of the sequential code elements. In the method the code elements are scanned by the scanning beam or by a plurality of scanning beams of a bar code reader along scanning lines extending substantial parallel to one another. During this the sweeping of the scanning beam over the bar code defines a scan and a scanning plane is defined by each scanning beam when sweeping over the bar code. The angle of tilt between the respective scanning plane and A predetermined reference plane is determined for essentially each scan. During the decoding of the bar code the angles of tilt thus found are evaluated to compensate for grid errors, i.e. for irregular spacings between adjacent scanning lines. Furthermore, a method for the compensation of fluctuations in the scanning speed and also an apparatus for carrying out the method are described.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.