Study On Holographic Display Based On Compressed Sensing Theory

Holographic display is considered to be the most perfect three-dimensional display because it can actually reflect the object’s depth and color. The classic holography record the amplitude and phase of object wave through the interference between reference light and object light, the interference fringe image called hologram, and the object light is reconstructed by the reference light irradiating hologram. With the rapid development of computer technology, the holographic display achieves a new leap. The computer generates hologram through simulating the interference between object light and reference light, and hologram is loaded into spatial light modulator, the original image is reconstructed by the laser irradiate the spatial light modulator.Although the computer-generated hologram technology solves several influences in classical optical holographic display in the interference by external environment, the high requirements with recording medium and the low accuracy of recording device. The holographic display has failed to achieve the commercial standard, and one of the important factors for restricting its development is large amount of calculation. This is because of the limit of the sampling criteria which based on the currently sampling principle. However, the compressed sensing theory as a new theory, it breaks the basic theory of traditional digital signal processing. First, it samples.a small amount of valid data, and then the original signal data is reproduced by the reconstruction algorithm. The paper solve the problem of the holographic display with large amount of calculation, the method combined compressed sensing theory with holographic display technology, and reconstructed the original object by holographic display system based on spatial light modulator(DMD). The mainly completed work and innovation points in this paper are:1. Analysis of the basic theory of holographic display, including the basic principle of holography about Fresnel holography, Fourier holography and ray tracing holography, the typical computer-generated hologram process and two methods of making process of CGH about Burch code holography and Huang code holography. At last, several hologram methods were simulated by computer programming.2. Analysis of the basic theory of compressed sensing, including three main contents:signal sparse representation, measurement matrix selection, reconstruction algorithm. Research on the effects of different orthogonal basis dictionary and structure over complete dictionary for the sparse representation of image in signal sparse representation. The experiment results indicate that the image can be clearly reconstructed by using the wavelet orthogonal basis dictionary and over complete dictionary for the sparse representation of image.3. A new hologram coding and reconstruction algorithm based on compressed sensing theory and lensless Fourier transform is proposed. Firstly, lensless off-axis Fourier hologram is generated by computer, and then the hologram is sampled and reconstructed by the theory of compressed sensing. At last, the original image is reconstructed by the hologram. In addition, a holographic reconstruction system is built to verify the hologram compression sampling theory. The experimental results indicate that the original image can be clearly reconstructed by the system, which proves the feasibility of the method.4. The encoding and reconstruction algorithm of the pure phase hologram based on compressed sensing theory is proposed. Firstly, scene data are sampled and reconstructed by the theory of compressed sensing theory. Secondly, according to the recovered data, error reduction algorithm is used to get the pure phase hologram. In addition, it has been further verified by the holographic reconstruction system based on silicon-liquid crystal, and the results indicate that the original image can be clearly reconstructed by the system, which proves the feasibility of the method.