Viewing-angle characterization of reflective-type liquid-crystal displays by using an ellipsoidal mirror and a two-dimensional CCD camera

摘要

A new photometry to perform the viewing-angle characterization for reflective-type LCDs has been developed. The optics consists of a rotating ellipsoidal mirror and a 2-D CCD camera. The information obtained by this photometry includes the viewing-angle characteristics of reflectance, contrast ratio, and chromaticity coordinates, which are comparable to gonioscopic photometry in terms of accuracy. Both the illuminating polar angle and azimuth angle can be scanned. The meas- urement time for this method is as short as that for conoscopic photometry when using a 2-D CCD camera. An instrument equipped with light-polarizing devices is already available. If analytic software was available, viewing-angle characterization could be determined by a polarization analysis.