Complex modulation computer-generated hologram by a fast hybrid point-source/wave-field approach

Abstract

International audienceWe propose a fast Computer-Generated Hologram (CGH) computation method based on a hybrid point-source/wave-field approach. Whereas previously proposed methods tried to reduce the computational complexity of the point-source or the wave-field approaches independently, our method uses the two approaches together and therefore takes advantages from both of them. The algorithm consists of three steps. First, the 3D scene is sliced into several depth layers parallel to the hologram plane. Then, for each layer, we compute the complex wave scattered by this layer either using a wave-field or a point-source approach according to a threshold criterion on the number of points within the layer. Finally, we sum up the complex waves scattered by all the depth layers in order to obtain the final CGH. Experimental results reveal that this combination of approaches does not produce any visible artifact and outperforms both the point-source and wave-field approaches

Hybrid approach for fast occlusion processing in computer-generated hologram calculation

“…The outlines of the method can be found in [36]. Compared to [36], this paper provides the mathematical demonstration of our algorithm, a detailed description of the GPU implementation and a thorough analysis of numerically and optically reconstructed scene images.…”

“…The outlines of the method can be found in [36]. Compared to [36], this paper provides the mathematical demonstration of our algorithm, a detailed description of the GPU implementation and a thorough analysis of numerically and optically reconstructed scene images. Section 2 gives an overview of the proposed method, Section 3 and Section 4 present respectively light propagation and light shielding techniques used by the method, Section 5 explains how the depth layers are classified, and Section 6 gives a detailed description of the GPU implementation.…”

Fast generation of complex modulation video holograms using temporal redundancy compression and hybrid point-source/wave-field approaches

“…As shown in this figure, the proposed method does not produce any visible artifact, even at the boundaries between the two categories of scene points. In order to evaluate the objective quality of the reconstructed images compared to the hybrid method proposed in [26], we used the Peak Signal-to-Noise Ratio (PSNR). The PSNR of the reconstructed images were found to be higher than 50dB for each video frame.…”

“…These experimental results show that the CGH pattern is accurately updated at each video frame and that the proposed method does not reduce the quality of the reconstructed scene images compared to the hybrid method. In order to evaluate the performance of the proposed method in terms of computation time, we compare it with GPU implementations of four other methods: (1) the method proposed in [32], based on a wave-field approach, (2) the method proposed in [11], based on a point-source approach, (3) the method proposed in [28], based on a point-source approach and incremental update of the CGH at each frame, and (4) the method proposed in [26], based on a hybrid approach. In the following, these methods are called wave-field method, point-source method, incremental method and hybrid method, respectively.…”

“…As a consequence, these two approaches are rarely fully efficient for computing holograms of real scenes in their entirety. In order to overcome these limitations, a new hybrid point-source/wave-field approach has recently been proposed [26]. In this approach, the scene is sliced into several depth layers parallel to the hologram plane.…”