Development of picture colorimeter using a liquid crystal tunable filter and a monochrome CCD camera

摘要

We developed the picture col orimeter that was composed of infrared eliminating filters, a Li quid Crystal Tunable Filter (LCTF) and a monochrome CCD camera. The infrared eliminating filters were necessary to eliminate infrared affection because the LCTF had a sub-band in the infrared region and the CCD camera was sensitive to the infrared light. Peak wavelength of spectral transmittance of the LCTF can be adjusted electrically. Eight wavelengths were selected and the coefficients to integrate outputs of the CCD camera from 8 spectral regions were determined so that the integrated spectral sensitivity of the system resembled the CIB color matching functions. Validity of the system was tested by comparing tristimulus values, X, Y and Z obtained from the present system and from a commercial spectro-radiometer. The results showd fairly good agreement between them.