Real-time holographic 3D display using Split–Lohmann Fresnel computer-generated hologram (SL-FCGH)

Real-time generation of computer-generated hologram (CGH) from three-dimensional (3D) objects has been a long-standing problem in holographic display. In this paper we report a fast CGH generation algorithm, which can rapidly synthesize a 3D Fresnel hologram in only one-step backward propagation calculation in a Split-Lohmann lens-based diffraction model. In such a calculation scheme, we utilize an image padding and cropping strategy to remove image artifacts and improve the display quality in a large depth range. The generated hologram, which is called Split-Lohmann Fresnel CGH (SL-FCGH), can reproduce 3D images through free-space Fresnel diffraction optics. The computation time of the proposed method is independent of the quantized layer numbers and, therefore, can achieve real-time computation speed with a very dense depth sampling. Both simulation and experimental results of full-color holographic display prove the validation of the proposed method.