We proposed a method for calculating the computer generated hologram from multi-plane 3D objects by using nonuniform sampled angular spectrum method （NUASM）. Both of the holo-gram plane and the image plane are nonun...We proposed a method for calculating the computer generated hologram from multi-plane 3D objects by using nonuniform sampled angular spectrum method （NUASM）. Both of the holo-gram plane and the image plane are nonuniform sampled according to the distances and positions of the three-dimensional objects. The nonuniform fast Fourier transform （NUFFT） is used to calculate the angular spectrum propagation from the image plane to the hologram plane and the hologram can be calculated in only one step. Simulation and optical experiment results show that the hologram generated in this way can reconstruct objects on multi- planes simultaneously and separately without axial distortion.展开更多
The bidirectional error diffusion(BERD) algorithm is free from random phase modulation that introduces speckle noise on the reconstructed images, compared with other computer-generated phase-only hologram(POH) approac...The bidirectional error diffusion(BERD) algorithm is free from random phase modulation that introduces speckle noise on the reconstructed images, compared with other computer-generated phase-only hologram(POH) approaches. During the POH generation process, the amplitudes of all pixels are traditionally set to one for diffusing the errors to their neighborhood of unprocessed pixels. In this paper, we reveal that the reconstruction quality depends on the uniform amplitude value for different object pattern. The pattern-adaptive BERD(PA-BERD) algorithm is proposed for high-quality holographic reconstruction. The optimized amplitude value can be acquired for each object pattern and each propagation distance.The PA-BERD-based POHs have shown higher reconstruction quality than traditional BERD-based POHs in simulations as well as optical experiments.展开更多
文摘We proposed a method for calculating the computer generated hologram from multi-plane 3D objects by using nonuniform sampled angular spectrum method （NUASM）. Both of the holo-gram plane and the image plane are nonuniform sampled according to the distances and positions of the three-dimensional objects. The nonuniform fast Fourier transform （NUFFT） is used to calculate the angular spectrum propagation from the image plane to the hologram plane and the hologram can be calculated in only one step. Simulation and optical experiment results show that the hologram generated in this way can reconstruct objects on multi- planes simultaneously and separately without axial distortion.
基金the National Natural Science Foundation of China(NSFC)(Nos.61827825 and 61775117)the Tsinghua University Initiative Scientific Research Program(No.20193080075)。
文摘The bidirectional error diffusion(BERD) algorithm is free from random phase modulation that introduces speckle noise on the reconstructed images, compared with other computer-generated phase-only hologram(POH) approaches. During the POH generation process, the amplitudes of all pixels are traditionally set to one for diffusing the errors to their neighborhood of unprocessed pixels. In this paper, we reveal that the reconstruction quality depends on the uniform amplitude value for different object pattern. The pattern-adaptive BERD(PA-BERD) algorithm is proposed for high-quality holographic reconstruction. The optimized amplitude value can be acquired for each object pattern and each propagation distance.The PA-BERD-based POHs have shown higher reconstruction quality than traditional BERD-based POHs in simulations as well as optical experiments.
