Huan Deng

An integral-imaging three-dimensional display with wide viewing angle

— The viewing angle and flipping areas of a conventional integral-imaging three-dimensional (3-D) display were analyzed. The pitches of the elemental image and micro-lens are identical. The more micro-lenses used, the smaller the viewing angle becomes and the wider the flipping areas become. In this paper, an improved integral-imaging 3-D display is presented. The pitch of the elemental image is larger than that of the micro-lens. The single-viewing angles of all micro-lenses converge and there are no flipping areas at the optimal viewing distance. Computational reconstructions of improved and conventional integral imaging were carried out, and experimental results demonstrate that improved integral-imaging 3-D displays have a wider viewing angle than the conventional ones and do not have flipping areas at the optimal viewing distance.

Dual-view integral imaging three-dimensional display

In this paper, we propose a dual-view integral imaging (DVII) three-dimensional (3D) display that presents different 3D images in the left and right viewing directions simultaneously. The DVII 3D display consists of a display panel and a microlens array, and its elemental image array (EIA) is composed of two sub-EIAs. The sub-EIAs captured for two different 3D scenes are responsible for two different 3D images in the left-view and right-view integral imaging 3D displays, respectively. A prototype of the DVII 3D display using a pinhole array is developed, and good results are obtained.

Tilted elemental image array generation method for moiré-reduced computer generated integral imaging display.

In this paper, we propose a tilted elemental image array generation method for computer generated integral imaging display with reduced moiré patterns. The pixels of the tilted elemental image array are divided into border pixels and effective pixels. According to the optimal tilted angle, the effective pixels are arranged with uniform arrangement. Also, a pixel mapping method is proposed. Appropriate experiments are carried out and the experimental results show that not only the color moiré patterns are reduced remarkably, but also the resolution of the reconstructed 3D images are improved through the proposed method.

Depth Calculation Method of Integral Imaging Based on Gaussian Beam Distribution Model

In this paper, we propose a concept of the optimal viewing distance range and a depth calculation method of integral imaging. By considering the light emanating from a single elemental image point as a Gaussian beam, we analyze the integral imaging depth range and deduce the depth calculation formulas in different display modes. Experiments in focused mode were carried out, and good results finally confirmed the feasibility of the proposed method.

Partially-overlapped viewing zone based integral imaging system with super wide viewing angle

In this paper, we analyze the relationship between viewer and viewing zones of integral imaging (II) system and present a partially-overlapped viewing zone (POVZ) based integral imaging system with a super wide viewing angle. In the proposed system, the viewing angle can be wider than the viewing angle of the conventional tracking based II system. In addition, the POVZ can eliminate the flipping and time delay of the 3D scene as well. The proposed II system has a super wide viewing angle of 120° without flipping effect about twice as wide as the conventional one.

Realization of Undistorted and Orthoscopic Integral Imaging Without Black Zone in Real and Virtual Fields

When integral imaging systems work in their conventional configuration, the reconstructed images are pseudoscopic. The two-step pickup process is capable of giving an orthoscopic image, but it involves black zones, which affect the viewing angle. We analyze the black zones on the elemental images. The improved two-step pickup process is proposed to solve this problem, and the mathematical models of the improved digital secondary pickup process without black zones are also proposed. The simulation and experiment are presented. An undistorted and orthoscopic 3-D scene without black zones is reconstructed in real and virtual fields simultaneously.

Encrypting three-dimensional information system based on integral imaging and multiple chaotic maps

Abstract. An encrypting three-dimensional (3-D) information system based on integral imaging (II) and multiple chaotic maps is proposed. In the encrypting process, the elemental image array (EIA) which represents spatial and angular information of the real 3-D scene is picked up by a microlens array. Subsequently, R, G, and B color components decomposed by the EIA are encrypted using multiple chaotic maps. Finally, these three encrypted components are interwoven to obtain the cipher information. The decryption process implements the reverse operation of the encryption process for retrieving the high-quality 3-D images. Since the encrypted EIA has the data redundancy property due to II, and all parameters of the pickup part are the secret keys of the encrypting system, the system sensitivity on the changes of the plaintext and secret keys can be significantly improved. Moreover, the algorithm based on multiple chaotic maps can effectively enhance the security. A preliminary experiment is carried out, and the experimental results verify the effectiveness, robustness, and security of the proposed system.

High-optical-efficiency integral imaging display based on gradient-aperture pinhole array

Abstract. An integral imaging (II) display is proposed which consists of a display panel and a gradient-aperture pinhole array. The gradient-aperture pinhole array is symmetrical in both horizontal and vertical directions. The leftmost and rightmost pinholes are used to fix the horizontal viewing angle, and the uppermost and nethermost pinholes are used to fix the vertical viewing angle. To increase the optical efficiency, the aperture widths of other pinholes are gradually increased from both sides to the middle in the horizontal and vertical directions, respectively. A prototype of the proposed II display is developed. Its horizontal viewing angle is equal to that of the conventional one, while its optical efficiency is higher than that of the conventional one.

Dual-view integral imaging 3D display by using orthogonal polarizer array and polarization switcher

In this paper, a dual-view integral imaging three-dimensional (3D) display consisting of a display panel, two orthogonal polarizer arrays, a polarization switcher, and a micro-lens array is proposed. Two elemental image arrays for two different 3D images are presented by the display panel alternately, and the polarization switcher controls the polarization direction of the light rays synchronously. The two elemental image arrays are modulated by their corresponding and neighboring micro-lenses of the micro-lens array, and reconstruct two different 3D images in viewing zones 1 and 2, respectively. A prototype of the dual-view II 3D display is developed, and it has good performances.

Annular folded electrowetting liquid lens.

We report an annular folded electrowetting liquid lens. The front surface of the lens is coated with a circular reflection film, while the back surface of the lens is coated with a ring-shaped reflection film. This approach allows the lens to get optical power from the liquid-liquid interface three times so that the optical power is tripled. An analysis of the properties of the annular folded electrowetting liquid lens is presented along with the design, fabrication, and testing of a prototype. Our results show that the optical power of the proposed liquid lens can be enhanced from ∼20.1 to ∼50.2  m(-1) in comparison with that of the conventional liquid lens (aperture ∼3.9  mm). It can reduce the operating voltage by ∼10  V to reach the same diopter as a conventional liquid lens. Our liquid lens has the advantages of compact structure, light weight, and improved optical resolution.