A Calibration And Drive Circuit Design For LCoS Holographic Display

In recent years,3D display has gradually become the pursuit of display,its authenticity and immersive experience brings a distinctive visual experience.Holographic display is the ultimate goal of display as a technology that can truly reproduce object light wave.Holographic system based on spatial light modulator is the mainstream CGH platform at present.The computational hologram algorithm,the performance of spatial light modulator,optical path design are the important factors which affect the dynamic display and color display of hologram,which has also become the focus of researchers.Therefore,after analyzing and discussing structure of the holographic system,this paper determines the timing color display scheme based on LCoS,and designs a color holographic display system with high frame rate.The main work contents are as follows:1.A calibration method and test scheme for gray phase consistency are proposed.Firstly,the structure,modulation principle,gray scale linear consistency,resolution and other parameters of the device LCoS in holographic display are analyzed.The analog correction is aimed at the nonlinear response problem of liquid crystal,which adjusts the 0-255 gray scale voltage threshold by modifying the voltage value of the fixed gray scale voltage point.In order to solve the problem of gray phase curve deviation at different positions,a 5×5 grid linear fitting scheme with configurable parameters was designed.Through the analysis of double-slit interference fringes,the phase consistency of the latter corrected improved by 29.05%,and the corrected hologram has better definition and contrast.2.The hardware implementation method of holographic correction and display system based on LCoS is proposed.The data path of the whole system is divided into data input module,flatness correction module,DDR cache module,output module and laser lamp driver module.According to the principle of time-series color display,data is read,written and cached through the mode of DDR read-write bandwidth poling.This scheme is integrated in Vivado and burned to FPGA.The output hologram has a resolution of 1920×1080 and a frame rate of 360Hz.Finally,color hologram is made and optical system is built to realize color hologram imaging.3.The simulation platform based on NC-Verilog and Matlab is used to verify the function and logic synthesis of the calibration system.The flatness correction module is combined with the I~2C module to realize the configurability and portability of the correction system.Under the process of 0.18?m,the module area is estimated to be113335.03?m~2.The innovation point of this paper is proposed a set of correction scheme and spatial timing drive scheme for calibrating the linear phase characteristics of LCoS,and then put forward and implemented on FPGA,and the correction scheme is implemented on ASIC,at last a color holographic display system is built.