Evaluation between methods for the color measurement in holograms by using a CMOS-RGB camera and a spectrometer

Many models and methods commonly used in colorimetry have been incorporated to the study and knowledge of the colorimetric properties in the reflection color holograms; these methods have reported the possibilities of color reproduction in holograms. One method is based in calculating the color differences between the CIE-L*a*b* coordinates of the original object compared to the same values obtained for the reconstructed hologram; these values are calculated through the measurement of the spectral composition of the light in the reproduced hologram which are made with spectrometers. Other methods are based in the use of cameras for the color measurement, although, they are not commonly used for that ending in holography. This work presents the results of a comparative study between the use of spectrometers and RGB digital cameras for the color measurement in holograms. The diffraction efficiency of the holograms for a GretagMacbeth Colorchecker samples is measured through a spectrometer and their CIE-L*a*b* coordinates are calculated; the color differences are also calculated by taking as theoretical values the coordinates of the original object. A similar procedure is made by capturing the reconstructed images of the hologram through a CMOSRGB camera, which requires a linearizing and characterizing procedure. The RGB coordinates of the original object are compared with the RGB coordinates of the reproduced hologram too.