Method and apparatus for providing improved color correction in a subtrative color printing system
US4839722A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 30, 1987 |
| Grant date | Jun 13, 1989 |
| Priority date | — |
| Expiry date | Oct 30, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/6033
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An improved color correction apparatus for improved color printing in a subtractive color printing system is disclosed. The disclosed apparatus utilizes an optimized three-dimensional look up table of pigment density values addressed by primary color values. The look up table is created by printing a plurality of pigment bars in response to known input density signals to a laser beam for each of three color pigments used in the system. Each of these sets of bars is subsequently scanned by the input scanner to determine the spectral content of the resultant bars and thus create a plurality of color pigment values corresponding to the spectral content of each bar for each color which is a complementary color of one of the pigments. These characteristics are used to calculate the spectral content of an actual printed image generated in response to an image generated by an input triplet to the system. Numerical methods are used to alter the pigment signal outputs, subsequently recalculate the spectral content of an actual image, and to repeat these steps until the error between the spectral content of an image pixel from the scanner and the spectral content of the reproduced printed im…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.