Method for characterizing an LCD projection display

In this study, the characterization method for a typical desktop LCD color projector is reviewed. Measurements were made with a spectroradiometer to establish the additivity of the primaries, inter-channel dependence, color gamut, tone scale, contrast, spatial non-uniformity, temporal stability and viewing angle variation. In the case of tone characterization, LCD projectors show S-shaped curve between input digital values and output luminance unlike the conventional CRT monitor represented by a power function. Mathematical models to predict the S-shaped electro-optical transfer function have been empirically derive.d Four mathematical models including PLCC, GOG, S-Curve Model I and II were compared for their accuracy in predicting the colors generated by the display for arbitrary signal inputs. It is proven that the newly derived S-Curve Model I and II work successfully for an LCD projector.