Colorimetric Characterization of a Computer-Controlled Liquid Crystal Display

A new method was used to characterize computer- controlled liquid crystal displays (LCDs). The characteriza- tion, which was performed to enable colorimetric image display, included channel independence, spatial indepen- dence, screen uniformity, and colorimetry. The colorimetric model consisted of three one-dimensional look-up tables (LUTs) describing each channel's optoelectronic transfer function and a 3 4 matrix transformation that included black-level flare. The matrix coefficients were estimated statistically by minimizing the average CIEDE2000 color difference for a data set sampling the display's colorimetric gamut. The LUTs were recreated dynamically throughout the optimization of the matrix coefficients. The character- ization was implemented with three different instruments to evaluate the robustness of the method with respect to mea- surement uncertainty. The average performance ranged be- tween 0.1 and 0.4 E00 and was well correlated with instrument precision. The optimization approach improved performance by a factor of two compared with direct mea- surements. Despite differences in instrument design, the chromaticities of each primary following optimization and black-level flare compensation were very similar. This ex- cellent performance was a result of the display's optoelec- tronic properties well matching the model assumptions. The technique was also used to characterize three additional LCD displays ranging in their matching of the model as- sumptions. In this case, performance worsened. For one display, more complex models would be required for col- orimetric characterization. Finally, a colorimetric charac- terization based on measurements at the center of the dis- play and perpendicular to the face was used to predict measurements at the edges and at different angles. The results indicated that characterizations would be required at multiple positions and angles in order to achieve suffi-

[1]  Roy S. Berns,et al.  A Psychophysical Experiment Evaluating the Color Accuracy of Several Multispectral Image Capture Techniques , 2003, PICS.

[2]  Gabriel Marcu,et al.  Gray tracking correction for TFT-LCDs , 2003, IS&T/SPIE Electronic Imaging.

[3]  Roy S. Berns,et al.  Color managing the third edition of Billmeyer and Saltzman's Principles of Color Technology , 2002 .

[4]  Yasuhiro Yoshida,et al.  Color Calibration of LCDs , 2002, Color Imaging Conference.

[5]  Roy S. Berns,et al.  A psychophysical experiment evaluating the color and spatial image quality of several multispectral image capture techniques , 2004 .

[6]  Jason E. Gibson Colorimetric Characterization of Three Computer Displays (LCD and CRT) , 2000 .

[7]  R. Berns Billmeyer and Saltzman's Principles of Color Technology , 2000 .

[8]  Naoya Katoh,et al.  An Accurate Characterization of CRT Monitor (I) Verifications of Past Studies and Clarifications of Gamma , 2001 .

[9]  Norimichi Tsumura,et al.  Masking Model for Accurate Colorimetric Characterization of LCD , 2002, Color Imaging Conference.

[10]  Roy S. Berns,et al.  A generic approach to color modeling , 1997 .

[11]  Roy S. Berns,et al.  Estimating black‐level emissions of computer‐controlled displays , 2003 .

[12]  Michael H. Brill,et al.  Color appearance models , 1998 .

[13]  Roy S. Berns,et al.  Comparative Study of Metrics for Spectral Match Quality , 2002, CGIV.

[14]  Roy S. Berns,et al.  Spectral Color Reproduction Based on Six-Color Inkjet Output System , 2001, International Conference on Communications in Computing.

[15]  Mark D. Fairchild,et al.  Colorimetric characterization of the Apple studio display (Flat panel LCD) , 1998 .

[16]  Lindsay William Macdonald,et al.  Characterisation of a desktop LCD projector , 2000 .

[17]  Naoya Katoh,et al.  An Accurate Characterization of CRT Monitor (II) Proposal for an Extension to CIE Method and Its Verification , 2001 .

[18]  Mark E. Gorzynski,et al.  CRT colorimetry. Part II: Metrology , 1993 .