Picture quality stabilizer for a color laser printer
US6031629A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 7, 1998 |
| Grant date | Feb 29, 2000 |
| Priority date | — |
| Expiry date | Jan 7, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/6091
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In the picture quality stabilizer for a color laser printer, changes in the gray level characteristic and the color balance caused by changes in temperature and humidity are compensated in order to stabilize the reproduced image. The apparatus includes a temperature and humidity sensor, an upper-bound correction table, a gamma correction table and a mixed color correction table, each optimized with respect to a reference environment, interpolation means for those tables, and a gray level correction means for correcting the gray level with correction coefficients obtained by the interpolation means and the mixed color correction means for compensating any failure of the color balance with the linear transformation. With this configuration, the correction coefficients are so modified as to establish a stable gray level characteristic and color balance, and a stable reproduced image can be obtained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.