Research CGH And Three-dimensional Display

Computer-generated hologram is the combining product of computer technology and modern optics, quite different from traditional optical holography. We can produce hologram of real existing objects and virtual objects by computer-generated hologram technology. Computer-generated hologram technology does not require extremely strict optical setup and laser, so it has obvious flexibility. The CGH has a wide range of applications in optical encryption, interferometry, and three-dimensional display.This paper illustrates the basic method of CGH and summarizes several CGH encoding method. We introduce the CGH encoding method of Lohmann Ⅲ, modified off-axis reference beam CGH, kinoform, and computer-generated interference hologram. We made holograms by the above method, and reconstructed result was good.This paper studies the computer-generated hologram algorithm of three-dimensional objects. We have described the basic principles of planar layers method in detail. Three-dimensional object was layered according to different depths, and finally a synthetic hologram was made in this method, reducing the computational complexity and improving the computing speed. In order to obtain360°field of view, we give different depth values to different regions of the planar object,and we obtain several discrete holograms. These holograms are reconstructed respectively. In the end, we will obtain a three-dimensional object with360°field of view by synthesizing the reconstructed image.This paper studies the computer-generated cylindrical full-color hologram. Firstly, we introduce the algorithm of computer-generated cylindrical hologram based on hankel transform. Hankel transform was introduced into the algorithm of computer-generated cylindrical hologram, so FFT can be used in the calculation process of computer-generated cylindrical hologram to improve the computing speed. Firstly, we made a cylindrical hologram of a three-dimensional object using the algorithm of computer-generated cylindrical hologram based on hankel transform, and the reconstructed image was crisp. The algorithm of computer-generated cylindrical hologram based on hankel transform was applied to the computation of computer-generated cylindrical full-color hologram in this paper. We obtained the holograms of red, green, and blue color components of full-color three-dimensional object. We reconstructed the holograms respectively. In the end, the full-color three-dimensional object would be reconstructed by synthesizing the reconstructed images. The reconstructed result was good, and we could observe the reconstructed object from360°clearly.