Registering images on the front and on the back of a substrate using high resolution sheet measurement
US5930577A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 3, 1998 |
| Grant date | Jul 27, 1999 |
| Priority date | — |
| Expiry date | Aug 3, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G15/231
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Registering a first image on a first side of a substrate with a second image on a second side. A motor driven document transport advances a substrate to a transfer station that transfers the first image onto the substrate. The substrate is then inverted and the document transport moves the inverted substrate back to the transfer station to receive a second image. A sensor detects a leading edge and a trailing edge of the substrate, while an encoder operatively connected to the motor produces a predetermined number of pulses per revolution. A counter counts the number of encoder pulses between the leading edge and the trailing edge. The controller then determines the width of the substrate from the number of counted encoder pulses and from the distance the substrate advances per encoder pulse. The controller then controls the document transport to position the substrate at the transfer station such that the second image is registered with the first image.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.