Electro-optic barcode reader
US5471043A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 15, 1994 |
| Grant date | Nov 28, 1995 |
| Priority date | — |
| Expiry date | Apr 15, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K7/10762
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An optical assembly and electronic reader circuit cooperate to provide a highly-efficient and low-cost electro-optic barcode reader. The optical assembly includes a shielded housing, a photo detector and optical elements disposed about an un-folded optical path that provide a virtual reading window at one end of the housing whose field of view, which is focused to a point at the photo detector, is shaped to be no wider than constitutive barcode indicia. The electronic reader circuit includes a pulse amplifier and manual-adjustment-free average D.C. offset negative feedback and A.C. information peak detect negative feedback loops that respectively maintain the electrical pulse stream input to the pulse amplifier within the dynamic range thereof and eliminate electrical pulse stream peak noise. A circuit is coupled to a comparator with hysteresis square-up stage to deactivate the comparator in the state of no input signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.