Synchronized, variable speed capstan motor drive system for facsimile recorder
US4388652A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 30, 1979 |
| Grant date | Jun 14, 1983 |
| Priority date | — |
| Expiry date | Apr 30, 1999 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/1135
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A system synchronously controls the advance of a recording medium or may be employed in a facsimile recording apparatus in which a modulated optical information beam is caused to scan or be swept across the recording medium as the medium is advanced in a stepwise manner. For this purpose, digital control circuitry including a programmable read only memory responds to a galvanometer synchronization signal, indicative of the beginning of a scan line, and selectively generates stepping motor advance signals in accordance with a look-up table stored in the memory as the beam scans the recording medium. By this action, the location in each successively recorded line at which the recording medium is stepwise-advanced is aligned in the direction of movement of the recording medium with a corresponding advance location for every other line irrespective of the rate of advance of the medium. As a result, banding, which would otherwise contribute to degradation in the recorded image copy, is effectively eliminated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.