Apparatus and method for mitigating colorant-deposition errors in incremental printing
US7417768B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 13, 2000 |
| Grant date | Aug 26, 2008 |
| Priority date | — |
| Expiry date | Nov 10, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K2215/0094
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
CDE is measured for each nozzle array, to enable modification of a mapping between input image data and intended printing marks to compensate for the CDE. Printing proceeds using the modified mapping, which is either an optical-density transformation of data to printing marks or a spatial-resolution relation between image data and intended pixel grid. The density transformation preferably includes a dither mask (but can be error-diffusion thresholding instead); the resolution relation includes scaling of image data to pixel grid. For some invention forms, CDE includes printing-density defects, measured and used to derive a correction pattern—in turn used to modify halftone thresholding. For other forms CDE includes swath-height error, but still this is measured and used to derive a correction pattern etc. For still other forms, however, CDE includes swath-height error and correction takes the form of scaling. When the halftoning forms are applied to plural-pass printing, a printmask is used to map the dither mask etc. to the nozzle array, enabling application of the correction to the mask. Halftone forms ideally uses a gamma function, though threshold or linear corrections are poss…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.