Search

Accurate, fast, and reliable modeling and optimization methods play a crucial role in designing light field display (LFD) system. Here, an automatic co-design method of LFD system based on simulated annealing and visual simulation is proposed. The process of LFD content acquisition and optical reconstruction are modeled and simulated, the objective function for evaluating the display effect of the LFD system is established according to the simulation results. In case of maximum objective function, the simulated annealing optimization method is used to find the optimal parameters of the LFD system. The validity of the proposed method is confirmed through optical experiments.

It is insufficiently powerful to compute multi-view images at a high enough frame or data rate to support high quality dynamic three-dimensional displays with the current computer software and hardware. According to the correspondence between lens position and elemental image, a real-time computer-generated content generation method for integral imaging based on cross perspective is presented. A GPU-driven rendering pipeline (GDRP) with geometry instancing and instance culling technique is designed, and the number of triangles processed in the rasterization stage is reduced greatly. Several virtual dynamic scenes including various materials and millions of vertices are used to verify the performance of the GDRP method in the experiment. Experimental results show that the frame rate can reach 60 fps with 3840 × 2160 resolution.

Advanced volumetric data three-dimensional (3D) display can provide depth cues than conventional two-dimensional. Here, an algorithm of view frustum shear transformation and ray casting integral to realize real-time volume data 3D display is presented. It is compatible with the existing volume drawing pipeline and robust for other types of 3D displays. Experimental results demonstrate that the volume data is clearly represented, and real-time frame rate is more than 30 fps under the condition of subpixel-level at 4K (3840×2160) resolution. Besides, its performance does not rely on the viewpoint number and viewing angle, therefore, it is very suitable for 3D display of large viewing angles and dense viewpoints.

Aberrations caused by optical lens refraction in a light-field display (LFD) are minimized based on real-time pre-rectification. A virtual optical lens with the high precision surface is developed the constructive solid geometry under minimum primitives to rectify the sampling rays, and the virtual lens exhibits the same response to different incident ray wavelengths as the real lens in the LFD optical domain. In addition, assembly misalignment is taken into consideration during the partitioning of the elemental image array so that all the elemental images and the covering lenses can be precisely aligned. After rectifying the sampling rays with the constructed virtual lens, the rays are launched in parallel in the GPU, and path tracing is conducted to shade the element image array. The proposed approach ensures the consistency of the integral photography and LFD processes, which minimize the distortion and increasing the depth of field for three-dimensional (3D) images. Experimental results verify the feasibility of our proposed method. The structural similarity index is improved by 0.1, and 3D images at different depths are correctly expressed. Only three primitives are introduced to the system as a whole, meaning that the extra computation has little impact on the rendering efficiency. Consequently, the real-time generation of 3D light-field images is possible.

Computer-generated multi-view (MV) image for the three-dimensional (3D) display with lenticular lens arrays based on the backward ray-tracing technique is presented. To overcome the limitations of the traditional ray-tracing technique, whose minimum operating unit is the pixel, the proposed method can be applied at the sub-pixel level. The quality of the generated 3D image is not reduced, in contrast to existing methods for converting 2D images to 3D. Compared to the previous each camera viewpoint independent rendering method, the backward ray-tracing technique directly renders the final MV image rather than all the single-viewpoint images. Accordingly, the total render time is substantially reduced. Experimental results show that our proposed method significantly increases the simplicity and efficiency of the rendering process, especially ensuring the resolution of the final MV 3D image. Experimental results for 3D display with the generated 32-viewpoint 3D images are presented.

A new efficient real time rendering method for 3D model called double depth-image-based rendering (DDIBR) is proposed, which realizes higher frame rates and better image quality. This method can not only utilize the traditional rasterization pipeline, but also implements the algorithm on GPU to accelerate the rendering process. The feasibility of the method is verified by qualitative and quantitative experiments. Compared with traditional methods, this method has higher rendering speed and better image quality. The results show that the DDIBR method can be applied to a scene over millions of vertices and the resolution of 3840 × 2160 at 20 frames per second.

Three-dimensional (3D) light field displays require samples of image data captured from a large number of regularly spaced camera images to produce a 3D image. Generally, it is inefficient to generate these images sequentially because a large number of rendering operations are repeated in different viewpoints. The current 3D image generation algorithm with traditional single viewpoint computer graphics techniques is not sufficiently well suited to the task of generating images for the light field displays. A highly parallel multi-view polygon rasterization (PMR) algorithm for 3D multi-view image generation is presented. Based on the coherence of the triangular rasterization calculation among different viewpoints, the related rasterization algorithms including primitive setup, plane function, and barycentric coordinate interpolation in the screen space are derived. To verify the proposed algorithm, a hierarchical soft rendering pipeline with GPU is designed and implemented. Several groups of images of 3D objects are used to verify the performance of the PMR method, and the correct 3D light field image can be achieved in real time.

A modified single-pass multiview rendering method is proposed to achieve real-time large viewing angle volume data three-dimensional (3-D) display. By modifying the volume rendering pipeline, the mapping of the synthetic image pixel and multiperspective information is directly accomplished in once rendering pass. And then shear-transformed ray is cast to integrate multiperspective information into the synthetic image used for 3-D display. Proof-of-concept experimental setups are constructed with the autostereoscopic 3-D display and the 3-D light-field display to demonstrate the proposed method without loss of generality. The experimental results show that the real-time frame rates of the autostereoscopic 3-D display and the 3-D light-field display are more than 30 and 60 fps at 4K (3840 × 2160) resolution, respectively. The rendering efficiency of the proposed method is irrespective of the viewpoint number and viewing angle size. In addition, it is not only compatible with the volume drawing pipeline but also robust to different types of 3-D displays based on pixel coding. A feasible way of applying 3-D display to the biological and medical fields is presented.

In an integral imaging (InI) display system, the deviation of the lens position results in blur and distortion of the reconstructed three-dimensional (3D) image. To achieve undistorted and real-time 3D images, an image correction method based on the backward ray tracing (BRT) technology is presented. By finding the correct pixel-to-ray correspondence, the origin and the direction of the light ray for every pixel in elemental image array (EIA) are reset, and the corrected 3D image is obtained based on the BRT technique. Experimental results demonstrate the feasibility and effectiveness of the proposed method, and the structural similarity (SSIM) index of the reconstructed 3D image increased by 20 ∼ 30% compared with that without calibrating. The frame rate of EIA generation is over 40 fps, which can realize real-time generation.

A novel high-speed integral image object-order rendering method based on reverse perspective technique is proposed. It can easily eliminate the pseudoscopic problem when integral image is worked on real mode. Optical reconstruction with 90 × 90 viewpoints is demonstrated. There is no any information redundancy during the rendering process. The good compatibility for common rasterization 3D models is other feature of our method by use of standard graphic library. The rendering efficiency of our method is improved by 10–30 times comparing with traditional non real-time rendering methods.

A high-efficient computer-generated integral imaging (CGII) method is presented based on the backward ray-tracing technique. In traditional CGII methods, the total rendering time is long, because a large number of cameras are established in the virtual world. The ray origin and the ray direction for every pixel in elemental image array are calculated with the backward ray-tracing technique, and the total rendering time can be noticeably reduced. The method is suitable to create high quality integral image without the pseudoscopic problem. Real time and non-real time CGII rendering images and optical reconstruction are demonstrated, and the effectiveness is verified with different types of 3D object models. Real time optical reconstruction with 90 × 90 viewpoints and the frame rate above 40 fps for the CGII 3D display are realized without the pseudoscopic problem.

The exiting simulation method is not capable of achieving three-dimensional (3D) display result of the light field display (LFD) directly, which is important for design and optimization. Here, a high-speed visual simulation method to calculate the 3D image light field distribution is presented. Based on the backward ray tracing technique (BRT), the geometric and optical models of the LFD are constructed. The display result images are obtained, and the field of view angle (FOV) and depth of field (DOF) can be estimated, which are consistent with theoretical results and experimental results. The simulation time is 1s when the number of sampling rays is 3840×2160×100, and the computational speed of the method is at least 1000 times faster than that of the traditional physics-based renderer. A prototype was fabricated to evaluate the feasibility of the proposed method. From the results, our simulation method shows good potential for predicting the displayed image of the LFD for various positions of the observer's eye with sufficient calculation speed.

We consider the replacement of standard single-mode fibers with ultra-low loss (ULL) fibers in an elastic optical network (EON). Different replacement strategies are proposed and compared in terms of bandwidth blocking probability. Simulations show that the OSNR-blocking-based strategy is the most efficient and that there is a saturation trend between the attenuation coefficient of ULL fibers and blocking performance improvement.