Decoder system for light pen bar code reader
US4146782A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 5, 1977 |
| Grant date | Mar 27, 1979 |
| Priority date | — |
| Expiry date | Aug 5, 1997 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K7/0166
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A manually supported reader for a bar code which comprises a plurality of parallel bars of varying widths employs an optical detector which generates an electrical output signal which is a function of the code as the detector is moved. The detector comprises a light source and a light sensor, optically arranged to reflect light off of that part of the bar code with which it is in contact, thereby varying the output signal of the detector each time a boundary of one of the bars within the code is traversed. A decoding network receives the output signal from the detector and determines the time required to traverse each successive bar. A signal associated with the traversal of each bar is compared with an internally generated criterian. As a result of the comparison, the bar associated therewith is classified as to its width. Based on that classification, the criterian is recalculated for comparison with the signal associated with the next bar scanned. The decoding circuitry can be implemented within computer software or hard wired.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.