| There are many advantages of holographic information display for it can reconstruct information without aberration. In recent years, many researchers pay much attention on real-time holography using spatial light modulator, especially for color holography. This paper did research on key technology for color holographic display using liquid crystal spatial light modulator(LC-SLM). The study composed of: theoretical analysis of image reconstruction from hologram loaded by pixelated spatial light modulator; Chromatism's analysis and compensation have been made in the process of color image reconstruction based on LC-SLM; The modulation property of LC-SLM used in our experiment has been tested and the phase hologram has been optimized based on the modulation property. At the end of this paper a color holographic display system has been built with time-sharing method.This paper did analysis on how images reconstructed form holograms loaded by LC-SLM based on Fourier optics theory. The images reconstructed by active area and dead area of spatial light modulator were respectively analyzed. The analysis it made pave the way to color holographic display using spatial light modulator. It paid attention on fill actor's affection to energy distribution of reconstructed image. This paper proposed to superimpose digital blazed grating to phase hologram to improve the energy of reconstructed image which has been verified by experiment. According to our analysis, with the fill actor of 87% of SLM, the energy of reconstructed image can be improved by 65.0% with one direction blazed grating and by 172.2 with two directions.In the process of color holography display, the reconstructed images were spoiled by chromatisms for spatial light modulator act as diffractive optical element. This paper analyzed the causes of magnification chromatism, transverse and longitudinal ones. Considering the merit of computer generated hologram, it proposed to resample object information to compensate magnification chormatism. Blazed grating with proper period and direction was loaded to holograms to compensate transverse chromatism. It also compensated longitudinal chormatism by adding quadratic phase distribution. The experiment shows that the methods we proposed are effective and without any hardware such as achromatic optical element.LC-SLM is the core device in the full color holographic display system. The theoretical model of phase modulation property for reflective SLM with nematic liquid crystal has been created. This paper built test system for reflective SLM based on principle of Twyman-Green interferometer. The modulation property of PLUTO-VIS is achieved for three colors red (670 nm), green (532 nm), blue (473 nm). The computer generated holograms we used are optimized according the modulation property with look up table method. A comparison has been made between reconstructed image with and without optimum. The result shows that the image quality has been improved significantly after optimum. This also verified that the phase modulation property achieved by us is correct. We also analyzed modulation property for oblique incidence. The analysis shows that the incident angle should be as small as possible.We built full color holographic display system based on PLUTO-VIS. It composed of R, G, B laser combined by dichroscope,the synchronous circuit for laser and information displayed on LC-SLM, the filter and expander for laser, spatial light modulator(PLUTO-VIS) and some other optical elements. For color break problem encountered in time-sharing method for color information display,this paper proposed to update time sequence chart of laser. The phenomenon of color-break has been removed and correct color information was achieved.
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