Automatic bar code reading system having selectable long range and short range modes of operation
US5340971A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 17, 1991 |
| Grant date | Aug 23, 1994 |
| Priority date | — |
| Expiry date | Sep 17, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K2207/1018
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Method and apparatus for automatically reading bar code symbols is disclosed. One aspect of the present invention concerns a method of reading bar code symbols using an automatic hand-holdable bar code symbol reading device. In general, the automatic bar code symbol reading device comprises a hand-holdable housing containing operative elements which provide an object detection field and a scan field each defined external to the housing. The method involves automatically detecting the presence of an object within the object detection field by sensing energy reflected off the object. In a preferred embodiment, the object sensing energy is IR radiation produced from an energy reflects off the object source disposed within the housing. In automatic response to the detection of the object within the object detection field, the hand-holdable device detects the presence of a bar code within the scan field using a laser beam produced within the housing. Then, in automatic response to the detection of a bar code in the scan field, the automatic hand-holdable bar code symbol reading device reads the detected bar code in the scan field by producing scan data signals from the detected bar code…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.