Research Of CGH Based On LCOS Spatial Light Modulator

About80%of information is obtained from vision. But the primary means of visual three-dimensional information is still two-dimensional for long time. People always utilize physical and mental perception to integrate the3D information. In order to meet requirement for three-dimensional information, Holography becomes most attractive technology to display3D images, because hologram includes all phase and intensity information of object. When observing the volumetric image, people can obtain all accurate depth cues that is similar to the original object, so holographic display technology is also regarded as ultimate display technology.The CGH is an important branch of modern optics. CGH has many advantages compared with traditional optical holography:easy to copy, little noise, wide applied range. It is the key technology to real-time, dynamic three-dimensional display which makes hologram by computer. In this paper, some discuss and research has been done including:First, paper outlines the development and domestic research status of holographic display and the CGH. The principle and classification of SLM is introduced.To set up CGH software platform which can produce different types of holograms and include modules of digital reconstruction and image processing,3700line program has been writed. The platform can preprocess the hologram calculated to make reconstructed image correct. The holographic reconstruction systems based on LCOS are set up. The Fresnel band based on LUT technology to calculate the hologram of three-dimensional object is proposed. The method regards3D object as computational points that has much advantages including following several aspects compared with traditional ways:1. short calculating time2. avoiding the crosstalk between with bands. At the same time, the influence of SLM’s grid structure is studied by means of theoretical calculation and digital simulation. As for in-line and off-axis hologram, the research of minimum and maximal recorded distance, as well as minimum and maximal reconstructed distance, is carried out in line with LCOS parameters. At the same time, Correct carrier frequency is calculated. The paper research the feasibility of3D holographic reconstruction by ways of computer simulation and optoelectronic reconstruction. Finally, Based on the holographic display systems in lab, the research of two-dimensional、three-dimensional holographic images is carried out. The result is discussed in detail. The3D model s hologram of different perspectives is calculated continuously. Real-time dynamic three-dimensional holographic reconstruction has been studied.