Multi-pass calibration in fixed printhead array printers
US8322811B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 17, 2009 |
| Grant date | Dec 4, 2012 |
| Priority date | — |
| Expiry date | Jan 31, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/4078
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Methods and apparatus herein provide for automated calibration of multiple printheads used in a multi-pass printing system. Aspects hereof print a plurality of gray scale printed patterns each printed pattern corresponding to a gray scale value for each of the multiple printheads. The printed patterns are then measured to determine the intensity (e.g., optical density) of each of the printed patterns. A measurement function is derived from the measured intensity and gray scale levels used to print each pattern. Calibrated transfer functions are then determined from the measurement function and target function where each calibrated transfer function relates, for a corresponding printhead, an input gray scale level of a pixel in an image to be printed to a calibrated gray scale level to use for the corresponding printhead when operating in multi-pass mode.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.