Color Research and Application, Vol.31, No.2, 102-108, 2006
Two-primary crosstalk model for characterizing liquid crystal displays
The conventional methods,for colorimetric characteriation of displays assume that the displays satisfy the constraints of primary chromaticity invariance across gray levels and primary channel independence. The liquid crystal displays (LCDs) that reasonably satisfy the two constraints have been accurately characterized with the conventional methods and black-level correction. For the LCDs that do not reasonably satify the two constraints, we propose a higher-order method for accurate colorimetric characterization. Two-primary crosstalk (TPC) is observed,for two tested LCDs that may be due to signal interference. We derive the crosstalk function and develop the TPC model for characterizing the LCDs, which comprises a set of the simultaneous equations with offset constants, one-color variables, and two-color-product variables. The results show that the accuracy of the TPC model is significantly improved compared with conventional device models and only slightly worse than the three-dimensional look-up-table (3D-LUT) model, while the numbers of measurement data are 49 and 512 for the TPC and 3D-LUT models, respectively, The average color difference of 224 test samples is about 2.0 (1976 CIELAB color difference formula) with the TPC model for the LCD monitor either with higher or with lower two-primary crosstalk. While the proposed TPC model yields improved characterization accuracy over conventional models, the TPC model is evaluated on only two LCDs of the same manufacturer. Thus. the generality Of the LCD crosstalk deficiency is unknown and should be determined in future research. (c) 2006 Wiley Periodicals, Inc.