Information reading system
US4192452A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 18, 1977 |
| Grant date | Mar 11, 1980 |
| Priority date | — |
| Expiry date | Feb 18, 1997 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K2207/1016
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A television camera for picking up a bar coded label is controlled to produce scanning lines contacting each other as by halving its vertical sync frequency, producing an elliptical beam, alternating narrow beams with wide beam, or utilizing wobbling technique. Also a raster formed of the scanning lines is stepwise rotated by a pulse motor. Alternatively a pair of horizontal and vertical deflection coils disposed in quadrature relationship with the other pair of similar coils are supplied with sawtoothed deflection currents varying in amplitude at predetermined equal intervals and in quadrature relationship with similar current supplied to the other coil pair. For spaced scanning lines, a video signal from the television camera affected by its after-images is blocked by a gate. Alternatively, the signal is subtracted from a video signal due to the preceding scanning line correlative to the same to remove the effect of the after-images.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.