Accurate Hologram Generation Using Layer-Based Method and Iterative Fourier Transform Algorithm

Random phase is always added to the object to diffuse the object light in computer-generated holograms. However, this addition causes considerable speckle noise in the reconstructed image. For improving the speckle noise problem, we propose a new method, which can reconstruct the 3-D object with higher image quality. A virtual intermediate plane is introduced between the object and the hologram plane. A three-dimensional object is first sliced into multiple layers according to their depth information. Then, each layer is added with uniform constant phase and propagates to the intermediate plane with an angular spectrum diffraction algorithm. Complex amplitude from each layer is added together as the desired distribution in the signal area in the intermediate plane. Then, the iterative Fourier transform algorithm is taken between the hologram and the intermediate plane to achieve the phase-only computer-generated hologram (CGH). Feasibility of the proposed method is verified with simulations and experiments.