| To achieve dynamic holography display, this paper studies the reconstruction of CGH (Computer-Generated H ologram) based on TFT-LCD (Thin-film-transistor Liquid Crystal Display). The CGH is displayed in TFT-LCD which is a SLM (Spatial Light Modulator), and the dynamic reconstructed image can be received. Due to the pixel structure of TFT-LCD, the reconstructed image can be deeply effect by the effect of BM (Black Matrix). Pre-studies always started with LCD devices, making the optical system complicated and difficult to carry out. Otherwise, the normalization method of CGH also effects the reconstruction, but almost no pre-studies are done. So, this paper does.Our studies include calculating CGH, simulating the reconstruction of CGH based on TFT-LCD, the effects of TFT-LCD pixel structure to the reconstructed image, eliminating the effect of BM and researching normalization methods of CGH.To calculate CGH, sampling, calculating and encoding must be done. The in-line and off-line optical reconstructions of CGH are introduced, also some algorithms of digital reconstruction. We use Burch-CGH to optical reconstruction and in-line-CGH to digital reconstruction.Computer is used to simulate TFT-LCD pixel structure and the reconstruction of CGH. The BM of TFT-LCD is simulated by 'Splitting Pixel Method' and the result is given. By simulation, the curvilinear relationship between TFT-LCD pixel structure and the reconstructed image is achieved, which is useful to choose out suitable TFT-LCD. 'Differential Compensation Method' is supposed to eliminating the effect of BM, receiving the ideal single reconstructed image and easily being processed, which has been demonstrated by computer simulation and optical experiments.This paper also discusses the influence of normalization to the fidelity and diffraction efficiency of CGH, generalizes the best normalization method to meet undistorted and high diffraction efficiency CGH, which makes good quality reconstructed image.
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