Method of collecting and adjusting bar code data from a laser bar code reader
US5608200A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 28, 1994 |
| Grant date | Mar 4, 1997 |
| Priority date | — |
| Expiry date | Nov 28, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K19/06028
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method is disclosed for processing bar code data obtained from a bar code label including large and small bars. A light source such as a laser beam scans across the symbol on a bar code label. Light reflected from the bar code label is collected as the light source scans across the label. The collected light varies in intensity as the light source scans across the label. An electrical signal is generated which is indicative of the amplitude of the light collected in the collecting step. The electrical signal is sampled at a predetermined data rate to produce a sequence of samples representative of the electrical signal. A sequence of samples is stored in a memory. These stored samples include label space values (LSA's). The samples also include label bar values (LBA's) which include large bar values and small bar values. The sequence of samples is decoded. The label space reflectance (LSR) is determined by dividing the product of the calibration space reflectance (CSR) and a label space value (LSA) by the calibration space average (CSA). The disclosed method also provides for the normalization of label bar values (LBA's).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.