Color calibration of displays
US6690383B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 24, 2000 |
| Grant date | Feb 10, 2004 |
| Priority date | — |
| Expiry date | Jan 24, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N17/04
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The present invention provides methods and apparatus for the color calibration of displays. These methods are particularly useful for displays having properties different than those associated with cathode ray tubes (CRT). Some displays, for example liquid crystal displays (LCD), have a high luminance black, the chromas of their primaries are not independent of their luminance levels, the intensities of their primaries are not strictly monotonically increasing with respect to their RGB levels, the color additivity of their subpixels is affected by crosstalk or leakage and their color measurements are dependent on the view angle of the observer. Therefore, the usage of CRT methods is deficient for such displays. The methods and apparatus of the present invention overcome several deficiencies generally found in non-CRT display devices by employing techniques associated with the use of restricted ranges for the primaries, subtracting the color black from all color measurements, forming a modified display matrix and/or creating tables which correct errors due to the non-linearities or color leakages of these display devices. These enable images to be processed using algorithms of diffe…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.