CCD-based system for two-dimensional measurement of color uniformity of LCD projector

摘要

A lower-cost monochrome CCD camera, which can detect the twenty-five frames of picture in one second, provides a rapid method to measure two-dimensional luminance distributions of the screen. According to the two-dimensional luminance distribution ratios of three primary colors captured by the CCD camera and the chromaticity coordinates of R, G, and B calibrated by the spectrometer, the chromaticity coordinates of combination colors of the LCD projector can be computed quickly. The algorithm of removing the black stimulus values and the precise calibration in five gray levels of CCD are employed to diminish the error. The two-dimensional distribution maps of chromaticity coordinates of combination colors of five levels are represented in this paper. The data show that the maximum difference between the chromaticity coordinate measured by CCD-based system and by the spectrometer is 0.009, which can present the color uniformity of LCD projector properly.