Symbol decoding method and means
US4074852A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 6, 1976 |
| Grant date | Feb 21, 1978 |
| Priority date | — |
| Expiry date | Dec 6, 1996 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K7/0166
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Symbol decoding method and means are provided for identifying special symbols such as "start of tag" and "end of tag" forming part of a record contained on record media or placed directly on articles or credit cards in coded form such as a bar code. Various clock frequencies are applied through gates to counters for periods of time corresponding to sensed characteristics such as width of various components of the coded record in such manner that the final condition of the counter at the completion of sensing of the symbol provides an indication of the identity of the symbol. The counters may be of the up-down type, so that clock signals corresponding to different code components can cause the counter to count in different directions. Two counters are employed for detection of each of the "start of tag" and "end of tag" symbols so that the testing for the symbols can be commenced with successive components of the code.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.