Fuwa-Vision

A high‐resolution autostereoscopic three‐dimensional (3D) display is proposed. It comprises two light source arrays (LSAs), a transparent liquid crystal display (LCD) panel, a scattering layer, and a lenticular lens. Light emitted from the LSAs is directed onto the transparent LCD panel, which projects the opening units corresponding to different parallax image pixels into distinct spatial locations, thereby creating new pixels. These new pixels are modulated and reconstructed by the scattering layer, incorporating both the original parallax image pixel information and the information from adjacent pixels post‐differentiation. Consequently, when the new pixels are projected through the lenticular lens to the viewpoint, a high‐resolution 3D image is displayed. The experimental results demonstrate the validity of our proposed autostereoscopic 3D display.

Mid-air display (MAD) technology is attractive to practitioners nowadays. The interest is due to the potential application in consumer products with embedded floating image displays, like smartphones, smartwatches and dock-stations, and as a part of new holographic user interfaces for safe and contactless control. Some of the problems to solve on the way to compact and light efficient MAD include small field of view, small image size, low image resolution, low image contrast, absence of image magnification, low perceived sense of depth, etc. In order to overcome these challenges, the authors propose a MAD based on a DMD pico-projector and a DOE waveguide with a positive Fresnel lens, placed near the out coupling aperture of the DOE waveguide. The developed MAD forms a real image with a positive relief from the display surface so that the viewer perceives this image floating in front of it, at the back focal plane of the Fresnel lens. For mid air image with ≥ 1-inch diagonal with 57 mm image relief horizontal field of view was 35 degrees, with image brightness 100 cd/m² . The proposed mid-air image display has a compact form factor with dimensions 100 mm × 50 mm × 3 mm, without dimensions of the DMD pico-projector. It can be used in consumer products to provide a new kind of experience including contactless holographic user interaction

A volumetric display system that creates a distortion-free three-dimensional (3D) image in midair using a novel imaging system is reported. A roof mirror array forms an aerial real image with an image deformation by retroreflection. The image deformation can be reduced by constructing an imaging system using two roof mirror arrays arranged in a parallel manner. A cross-sectional image of a 3D object is formed by the proposed imaging system in midair and swept by a galvanometer mirror scanner to create a 3D volume image. An aerial 3D volume image formation without the image deformation was confirmed by an experimental volumetric display system.

In this paper, we propose a novel interactive 3D information visualizing display that superimposes a cross-sectional image in an aerial volumetric image of an object. Figure 2 shows a system configuration. A user can see internal images of the object, such like an X-ray image, by inserting a semi-transparent handheld screen in a cloned floating image. We use two Micro Mirror Array Plates (MMAPs) to reproduce a Light Field Clone (LFC) image. The MMAP (Aerial Imaging Plate, ASUKANET. Co., Ltd.) was designed for reconstructing aerial images in midair based on double reflections. The LFC image is a reconstructed floating 3D image which can be seen without wearing any glasses. In the HaptoClone system [Makino et al. 2015], they proposed the use of two MMAPs to reproduce LFC image of the object. By contrast, we use additional two general mirrors in the proposed system. With this configuration, the realistic LFC image appears next to the object keeping the facing direction same. Users can see both the real object and its cloned image at the same time.

To improve angular dependence of liquid crystal displays(LCDs), three LCD configurations are proposed. Two of these configurations correspond to transmissive LCDs and the remaining one to reflective LCDs. Each configuration includes negative Δ n compensators whose optical axes take the similar liquid crystal director profile.

High concentrating photovoltaic (HCPV) technology plays a more and more important role in solar power generation due to its extremely high efficiency. However, the efficiency of the HCPV module can be reduced by many factors. Especially, there are not enough researches and knowledge on the light intensity distribution and non-uniform illumination of different wavelengths of light concentrated by Fresnel lens. It is generally considered that the maximum power of multi-junction solar cell is achieved when the cell is placed on the focal plane of Fresnel lens. But it is proved to be incorrect by our research. When light beams of different wavelengths go through the Fresnel lens, their light spot distributions on the optical axis are not the same as those when they have different refractive indexes in Fresnel lens. At the same time, the triple-junction solar cell consists of three sub-cells which absorb light beams of different wavelengths respectively. Therefore, the performance of triple-junction cells would be influenced by the light distribution along the optical axis, this is exactly what we want to study in this work. The method of simulating the light tracing is used to calculate and analyze the light intensity distribution and non-uniform characteristics of different wavelengths of light concentrated by Fresnel lens. Combined with them from the circuit network model of a triple-junction solar cell, the electrical performances of triple-junction solar cell at different positions along the optical axis are studied. It is found from the simulation that the performance of cell does not reach the best state when cell is placed on the focal plane. The power of cell on the focal plane reaches only 0.41 W while the maximum point arrives at 0.69 W. The high non-uniformity of light on cell surface when cell is placed on the focal plane causes the decline of power. And an outdoor HCPV testing system with the ability to change the distance between Fresnel lens and the cell is conducted. The experimental results and the simulation results match well, therefore our simulation approach is verified. It shows that the module achieves the maximum power on either side of the focal plane, and the output power can increase more than 20% after optimization. It is a result after equilibrium between light intensity and uniformity on cell surface.

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] Airy beam is a self-sustained light beam that propagates in free space along a parabolic trajectory with a constant lateral acceleration. It is a diffraction-free beam with an electric field pattern described by the Airy function containing a main lobe and side lobes. Unlike Gaussian beam that expands after the focus, a practical finite-energy Airy beam keeps its pattern without spreading over a relatively long distance during its propagation. This unique feature makes the Airy beam a great potential of designing optical systems for three-dimensional (3D) imaging. In this work, we develop a new optical 3D imaging methodology using Airy beam. The proposed imaging method has an advantage of increased depth of field (DOF) that is important in biological optical imaging. In the first step, we perform a fundamental research on specific parameters that can affect the properties of the Airy beams. The finite-energy Airy beams are generated by optical Fourier transform using a lens with the incoming plane wave that is truncated by an aperture. Our simulation and experiments showed that by changing the aperture size and the focal length of the lens, the Airy beam pattern is modified. In addition, the DOF, the beam size and the main lobe energy are changed. As a result, Airy beam can be designed for specific imaging applications. Next, we consider the phase in the cubic phase pattern for the phase modulation to generate the Airy beam. This problem is related to the wavelength dependent phase modulation since the phase in cubic phase pattern is designed for a specific wavelength whereas a broadband light source is normally used in optical coherence tomography (OCT). A liquid crystal display (LCD) panel from a projector is used as the SLM. The cubic phase patterns with different gray values displayed on the computer screen provide different phase modulations in the SLM. The experimental and simulated results show that the phase modulation affects the beam shape of the Airy beam. If the maximum phase modulation is larger than 1.7pi, the Airy beam can keep its pattern and the unmodulated Gaussian beam can be neglected. Further, we design a 3D imaging system using the phase-space method based on the Wigner distribution function (WDF). We theoretically build the WDF for the Airy beam and show that the WDF of the Airy beam is shifted in the phase-space as the transverse position of incoming Airy beam changes, and the WDF is tilted as changing the axial position (along the propagation direction). A larger truncating factor can reduce the energy contribution in WDF for the side lobes and modify the shape of the main lobe close to a straight line. In this case, the WDF of the Airy beam is similar to that of the Gaussian beam. However, the DOF of the Airy beam is greatly improved. We perform experimental measurements of WDF using the basic idea of measuring both the space and spatial frequency information in a 4-f system. Our experimental results match the simulation and validate the 3D imaging using Airy beam in the phase space.

Sixty-four color LCD panels were employed to implement a natural 3D display. Sixty-four images displayed on the LCD panels are projected in the different horizontal directions by using modified 2D aligned telecentric optical systems. Because the projection angle pitch in the horizontal direction is as small as 0.33 degree, observers’ eyes can focus on the 3D images. Because the projection systems are telecentric, images are defocused little so that clear 3D images are generated in the 3D space. The horizontal viewing angle is 21.2 degrees, and the 3D screen size is 192 mm X 151 mm (9.6 inch.) The 3D objects can be displayed in the range of ~ 400 mm both in front of and behind the 3D screen. The prototype 3D display has following features: a) no need of wearing 3D glasses, b) simultaneous observation by multiple persons, c) no restriction on observing position, d) compatible with human 3D perception, e) providing high presence, and f) offering photorealistic and moving 3D images. The human accommodation responses to the prototype 3D display are very similar to those obtained for real 3D objects.

We propose a new and effective Light Guide Plate, called Empty Chamber Fresnel Lens Light Guide Plate (ECFL-LGP), to provide the merits of thin, lightweight, low-cost and high effect of light rays guiding for a medium or large LED-sourced Edge Lighting Backlight Module. It consists of a simple Empty Chamber and two sets of linear irregular Fresnel lenses. Due to the reasons that the structure of the Empty Chamber is simple and a Fresnel lens is thin and cheap, our ECFL-LGP will possess lower cost than the traditional hard LGP. On the other side, the irregular Fresnel lens in ECFL-LGP will be better than the traditional mesh-like dot about the effect of light rays guiding because its irregular linear groove angles can be evolved in terms of the optimization requirements of light rays guiding. As for the uniform problem of light rays guided to the LCD panel, we will design a double-deck linear irregular Fresnel lenses to act as a prismatic film according to the uniformity requirement. To overcome some problem caused by designing linear irregular Fresnel lenses, we propose an idea of dividing the designed Backlight Module into several sections to reduce the number of evolved groove angles, and dividing the design procedure into two stages: first, evolve two sets of linear irregular Fresnel lenses in the designed ECFL-LGP, then evolve four sets of linear irregular Fresnel lenses between the ECFL-LGP and the LCD panel. As a result, the thickness of the designed LED-sourced Edge Lighting Backlight Module will be 4.85 mm only (the LCD panel is not included).

동적 마스크를 사용하는 3D 집적영상 기술은 공간에 고해상도의 3D 영상을 디스플레이할 수 있다. 본 논문에서는 동적 마스크를 사용한 새로운 3D/2D 변환 집적영상 디스플레이 시스템을 제안한다. 제안하는 방법에 대하여 2개의 LCD 패널을 통하여 보여지는 영상에 따른 3D 모드, 2D모드 그리고 3D/2D 혼합 모드의 동작원리를 설명한다. 3D모드에서는 요소영상과 마스크 영상이 표시되고, 2D 모드에서는 광원영상과 2D 영상이 표시된다. 그리고 3D/2D 혼합모드에서는 영역별로 2D와 3D가 분리되어 동시에 디스플레이 된다. 제안한 방법의 유용함을 보이기 위해서 기초적인 실험을 수행하고 그 결과를 보고한다. 3D integral imaging technique with an active mask is capable of displaying real 3D images with high resolution in space. In this paper, we present a novel 3D/2D convertible integral imaging display system using an active mask. For the proposed method, the principles of 3D, 2D, and 3D/2D composed operations are explained according to the displayed images through two LCD panels. In 3D mode, the elemental images and the mask images are displayed in two display panels. On the other hand, the light source image and 2D image are displayed in 2D mode. In addition, 3D/2D mode is obtained using the spatial separation for 3D and 2D modes. To show the feasibility of the proposed method, we carry out the preliminary experiments and present the optical results.

Previous studies have found that preschoolers are confused about the relationship between two‐dimensional (2D) symbols and their referents. Preschoolers report that 2D images (e.g. televised images and photographs) share some of the characteristics of the objects they are representing. A novel Comparison Task was created to test what might account for these misattributions of the properties of 2D images. Three‐and‐a‐half‐ and four‐and‐a‐half‐year olds made comparisons between items presented in two of three formats simultaneously, i.e. as a real object and as an object appearing on television (TV), as a real object and as a photo of that object, or as an object appearing on TV and in a photo. Presenting the televised object or the photo of the object along with the real object aided performance; children indicated that televised objects and photos of objects no longer shared the properties of the real objects. Children also performed better when presented with two 2D images of the same object (the photo of the object and the televised image of the object). Although dual‐representation might account for these misattributions of the properties of 2D images, because children also performed better when two 2D images of the same object were present, other possibilities such as children using pictures as communicative devices and disregarding the pragmatics of the task should be explored. Copyright © 2010 John Wiley & Sons, Ltd.

Today's Field Programmable Gate Arrays (FPGA's) are in use to implement high performance image processing systems. In this paper it is used in implementation of a FPGA based digital camera system for image capturing and real time image processing. Image captured by a Complementary Metal Oxide Semiconductor (CMOS) camera's image sensor are initially stored in the FPGA device memory and then they are displayed on the Liquid Crystal Display (LCD) digital touch panel. The main goal of this proposed design implementation architecture is to implement and test advanced complex image processing algorithm. The device also supports the control of the Complementary Metal Oxide Semiconductor (CMOS) image sensor through the control of the Liquid Crystal Display LCD digital touch panel. Further the FPGA device has the ability to communicate with a Personal Computer (PC) through an interfaced Joint Test Automatic Generation (JTAG) for storing the images on to it and further processing. The structural element of this proposed architecture was chosen to be implemented on ALTERA's DE2 FPGA device.

A display system that does not require viewers to wear special glasses to see 3D images is useful technology. Conventional 2-views lenticular and parallax-barrier display systems have disadvantages such that horizontal resolution is reduced by half because each eye only sees half the pixels. We describe a method to generate orthogonal polarized parallax images and a thin stereoscopic 3D display with a polarized parallax barrier. The advantage of the polarized parallax barrier is that the resolution of presented parallax images is much greater than that possible with conventional displays. This compact display has liquid crystal display(LCD) panels and/or Electoro Luminescence(EL) devices to present stereo views and to control polarization. It has twice the 3D image resolution, because the image plane can multiplex images with horizontal and vertical polarization to display stereo views.

Multiview display is a popular method to deliver three-dimensional (3D) images by generating a perspective directional view. However, there are some limitations such as a low resolution, lack of motion parallax, and a narrow viewing angle. In this paper, we propose a method to implement a multi-view display system that provides a 3D image in high resolution. The original setup is composed of a stereoscopic 3D display panel and a head tracking camera. The directional view image of a 3D object is captured by a camera array and shown on a stereoscopic 3D display. A user interface is designed to control the hardware. An Intel RealSense sr300 camera is used to track the observer's viewing angle. The images are captured rotationally through a movable camera array in a 30-degree span. There are 71 and 3 views in the horizontal and vertical direction, respectively. The directional view information is displayed according to the observer's viewing direction as well as the head position. The observer can realize a high-resolution 3D image with smooth motion parallax. Most importantly, the proposed system interactively displays the exact view direction according to the user's viewing angle which feels more natural to the observer.

Thin network extraction from three dimensional (3D) images is a new issue in image processing. It is of major importance in medical vascular imaging for diagnostics, therapy planning and surgery. Here, the authors develop a framework for automatic vascular network extraction from the volumic image. The approach consists in treating the 3D image as a hyper-surface of IR/sup 4/. It is shown that the crest points of this hyper-surface correspond to the center line of the thin network in the image. Promising results are shown on synthetic and real vascular images.