Flexible and Stretchable Smart Display: Materials,Fabrication, Device Design,and System Integration

Recent technological advances in nanomaterials have driven the development of high‐performance light‐emitting devices with flexible and stretchable form factors. Deformability in such devices is mainly achieved by replacing the rigid materials in the device components with flexible nanomaterials and their assemblies (e.g., carbon nanotubes, silver nanowires, graphene, and quantum dots) or with intrinsically soft materials and their composites (e.g., polymers and elastomers). Downscaling the dimensions of the functional materials to the nanometer range dramatically decreases their flexural rigidity, and production of polymer/elastomer composites with functional nanomaterials provides light‐emitting devices with flexibility and stretchability. Furthermore, monolithic integration of these light‐emitting devices with deformable sensors furnishes the resulting display with various smart functions such as force/capacitive touch‐based data input, personalized health monitoring, and interactive human–machine interfacing. These ultrathin, lightweight, and deformable smart optoelectronic devices have attracted widespread interest from materials scientists and device engineers. Here, a comprehensive review of recent progress concerning these flexible and stretchable smart displays is presented with a focus on materials development, fabrication techniques, and device designs. Brief overviews of an integrated system of advanced smart displays and cutting‐edge wearable sensors are also presented, and, to conclude, a discussion of the future research outlook is given.     

集成成像3D信息获取技术

集成成像作为一种新型裸眼三维(3D)显示技术,能够完整获取3D信息并还原再现,是目前最具发展前景的裸眼3D显示技术之一。其中,对3D信息的完整获取通过记录场景不同角度的视差信息,并以微图像阵列形式进行呈现,不仅能够为集成成像显示提供3D内容,更作为一种多维度信息获取手段,在被遮挡场景的探测成像、目标识别、2D/3D信息加密和显微3D成像等多个领域得到应用。文中对集成成像3D信息获取的基本原理、不同类型的集成成像3D信息获取技术以及集成成像3D信息实时获取技术进行综述,并讨论现存的一些问题以及未来发展趋势。     

In‐Vehicle AR‐HUD System to Provide Driving‐Safety Information

Augmented reality (AR) is currently being applied actively to commercial products, and various types of intelligent AR systems combining both the Global Positioning System and computer‐vision technologies are being developed and commercialized. This paper suggests an in‐vehicle head‐up display (HUD) system that is combined with AR technology. The proposed system recognizes driving‐safety information and offers it to the driver. Unlike existing HUD systems, the system displays information registered to the driver's view and is developed for the robust recognition of obstacles under bad weather conditions. The system is composed of four modules: a ground obstacle detection module, an object decision module, an object recognition module, and a display module. The recognition ratio of the driving‐safety information obtained by the proposed AR‐HUD system is about 73%, and the system has a recognition speed of about 15 fps for both vehicles and pedestrians.     

128 × 128 deformable mirror device

The deformable mirror device (DMD) is anX-Yarray of deformable mirror elements addressed by an underlying array of MOS transistors. Applications include optical information processing and projection displays. The architecture, operation, and experimental results are presented for a 128 × 128 DMD.     

变形网格及其在图像识别中的应用

网格特征是图像识别中一类重要特征,而变形模板对于复杂的图像识别问题如字符识别、数字识别、图标识别等表现出很好的性能,但变形模板很费时。该文针对网格特征提出了变形网格,并分析了变形模板与变形网格之间的近似等价性。所提方法对网格进行变形而不是对图像变形,因而速度比变形模板快得多,而且性能相差不大。把这种方法分别应用于图标识别和脱机手写汉字识别。图标识别实验中变形模板使识别率提高了7.5%,而变形网格使识别率提高了7.3%、手写汉字识别实验中变形模板使识别率提高了6.1%,而变形网格使识别率提高了5.8%。考虑到变形网格比变形模板快得多,所以这种方法是有优势的。     

Augmented System for Immersive 3D Expansion and Interaction

In the field of augmented reality technologies, commercial optical see‐through‐type wearable displays have difficulty providing immersive visual experiences, because users perceive different depths between virtual views on display surfaces and see‐through views to the real world. Many cases of augmented reality applications have adopted eyeglasses‐type displays (EGDs) for visualizing simple 2D information, or video see‐through‐type displays for minimizing virtual‐ and real‐scene mismatch errors. In this paper, we introduce an innovative optical see‐through‐type wearable display hardware, called an EGD. In contrast to common head‐mounted displays, which are intended for a wide field of view, our EGD provides more comfortable visual feedback at close range. Users of an EGD device can accurately manipulate close‐range virtual objects and expand their view to distant real environments. To verify the feasibility of the EGD technology, subject‐based experiments and analysis are performed. The analysis results and EGD‐related application examples show that EGD is useful for visually expanding immersive 3D augmented environments consisting of multiple displays.     

Physics-based integration of multiple sensing modalities for sceneinterpretation

The fusion of multiple imaging modalities offers many advantages over the analysis, separately, of the individual sensory modalities. In this paper we present a unique approach to the integrated analysis of disparate sources of imagery for object recognition. The approach is based on physics-based modeling of the image generation mechanisms. Such models make possible features that are physically meaningful and have an improved capacity to differentiate between multiple classes of objects. We illustrate the use of physics-based approach to develop multisensory vision systems for different object recognition application domains. The paper discusses the integration of different suites of sensors, the integration of image-derived information with model-derived information and the physics-based simulation of multisensory imagery     

表面传导电子发射显示技术进展

表面传导显示技术是结合了电子发射技术、微制造技术、CRT技术、大规模液晶显示器生产技术及半导体技术而研发出的新型平板显示技术。表面传导显示器除具有高亮度和高清晰度特性之外,还具有良好的频率响应特性、高对比度、高灰度级和低功耗等。本文对表面传导技术的诞生及发展进行了介绍,阐述了表面传导显示技术的显示机理及制作工艺,并就其发展前景和制约因素进行了分析。     

国外大屏幕和平板显示的一些发展

电视技术的发展和人们视觉特性的要求,尤其是HDTV的出现,使图象显示正在向高清晰度、高亮度、大屏幕、平板化方向发展。各种各样的新型显示技术和产品正在加紧研制开发和推出,图象世界正在进入百花争妍的时代。本文拟就大屏幕和平板显示的一些国外发展情况作一介绍。     

液晶投影显示器

CRT投影机的亮度和分辨率不能作到两全其美,以致不能满足工业与军用市场的许多更趣严格的要求。因此,人们的兴趣正在转向大量的光阀技术,其图像的写入采用电子束或激光束,而图像的亮度则靠投射灯来提供。在大量的光阀技术领域中,最活跃的领域是用电子束寻址或激光束寻址的液晶光阀投影显示器。本文则对许多液晶光阀器件的基本原理和工作特性作了评述。     

基于JPEG XR的半脆弱数字水印技术研究

研究并实现基于JPEG XR图像稳定性和内容认证的半脆弱数字水印技术。对JPEG XR图像的频率结构和码流结构进行了分析和研究,提取码流中每个分割块的DC系数和LP系数构造基于图像的二值信息,作为数字水印置乱后嵌入到原图像对应像素点YUV色彩空间的Y分量的最低有效位中,然后再对含有水印的图像进行JPEG XR再编码实现水印嵌入。通过比较基于图像的二值信息和嵌入在图像的二值水印信息,进行篡改定位。对含水印图像进行压缩、噪声、剪切等常见攻击实验,结果表明具有较好的稳定性和内容认证能力。     

扫描体素显示器

传统的立体显示器（stereoscopic display）需要观众人为地将眼睛的焦距固定在某一个距离,不断改变左、右眼收敛点来观察不同距离的物体,因此会造成眼疲劳和不适感,也降低了图像质量。立体显示器（Volumetric display）可以克服这个问题,但仅限于一定观看距离内和一定调节能力的小物体;同时,它们也不能正确地提供闭塞信号。本文描述了一种可能的解决办法——多平面扫描体素显示器（multi—planar scanned voxel display）。     

基于色度分析的唇动特征提取与识别

本文提出了一种基于色度滤波的唇动特征提取与识别方法 ,它通过唇的色度滤波 ,得到增强的唇动图像 ,再利用可变模板 ,描述口型轮廓并提取特征参数 ,并用HMM模型进行唇运动序列图像识别 .该方法鲁棒性强 ,对光照没有苛刻的要求 ,且针对非特定人 ,适用于自然条件下的实用环境 ,解决了可变模板对目标边缘有较高分辨率的要求 ,使方法更实用化 .本文的实验是基于单纯的视觉信息 (没有声音信道的信息 )的唇动识别 ,不加语音信息 ,实验集合只限于单韵母 ,识别率可达 95 8% .     

Integrated information modalities for human/machine communication: HuMaNet, an experimental system for conferencing

Ease of use is a major consideration as information systems become more sophisticated. A number of technologies for human/machine communication now permit natural interaction with complex systems for communication and computation. These technologies include automatic speech recognition, speech synthesis, audio and image compression, hands-free sound pickup, and hypertext methods for data base management. A digital teleconferencing system is described which integrates these information modalities for hands-free, voice-interactive operation. The system is implemented for voice, image, and data communication over public-switched commercial digital transport, namely, basic-rate ISDN.     

基于变形模板的多目标识别与定位

典型目标的识别与定位是无人机应用系统的关键技术之一,但实现完全地自动目标识别和定位存在一定的困难。该文提出一种采用变形模板进行多个目标的识别和定位方法,以机载传感器的融合图像为基础,并引入人在回路的思想,设计了基于变形模板的多目标识别和定位算法,重点研究了多目标变形模板库的构造和相应能量函数的定义,而变形模板的优化采用具有保优策略的遗传算法实现。仿真实验表明该方法具有较高的目标识别与定位能力,可以有效解决无人机图像中多个典型目标的识别与定位问题。     

基于小波变换的红外与可见光图像融合技术研究

随着传感器技术的发展,单一的图像传感器往往不能够从场景中提取足够多的信息,需进行多源图像融合.为了解决多传感器图像所表现的目标特征不一致的问题,本文采用小波变换对红外及可见光图像进行了融合.首先利用小波变换将图像进行多尺度分解.对于高频部分融合,取两幅图像小波系数矩阵对应元素的最大绝对值构造小波系数矩阵;针对低频部分融合,采用基于领域像素相关和基于区域方差相结合的策略.实验结果表明,该算法将红外与可见光图像对同一目标所表现出的不同特征、细节有效地融合在一幅图像里,增加了单幅图像的信息量,丰富了目标的信息层次,为图像显示观察和后续图像处理系统获取信息提供了基础.     

Technologies for Cofabricating MEMS and Electronics

Microfabrication technologies initially developed for integrated electronics have been successfully applied to batch-fabricate a wide variety of micromechanical structures for sensing, actuating, or signal-processing functions such as filters. By appropriately combining the deposition, etching, and lithography steps for microelectromechanical devices with those needed for microelectronic devices, it is possible to fabricate an integrated microsystem in a single process sequence. This paper reviews the strategies for cofabrication, with an emphasis on modular approaches that do not mix the two process sequences. The integrated processes are discussed using examples of physical sensors (infrared imagers and inertial sensors), chemical and biochemical sensors, electrostatic and thermal actuators for displays and optical switching, and nonvolatile memories. By adding new functionality to integrated electronics, the use of microelectromechanical systems is opening new applications in sensing and actuating, as well as enhancing the performance of analog and digital integrated circuits.     

用于柔性显示屏的驱动芯片连接技术

轻、薄、坚固、可弯曲的显示屏成为平板显示技术未来发展的重要方向，为了实现基于塑料衬底的柔性显示屏，驱动芯片的可靠组装连接成为关键。文章分析了现有的各种芯片组装技术的特点．同时基于柔性显示发展需求，提出了多种驱动芯片连接技术方案，并对各方案进行了比较。     

Trends in image display systems

Today, with large volumes of data, high throughput requirements, and more complex image processing algorithms, the emphasis is on interactive image processing. Consequently, image displays are beginning to occupy a central role in image processing architectures. This paper presents some historical background on image displays and identifies the functional capabilities required in today's displays. Provided next is a summary of current image display architectures and system design philosophy. The paper concludes with a projection of technology and indicates what impact these technologies will have on future display systems.     

Coaxial Thermoplastic Elastomer‐Wrapped Carbon Nanotube Fibers for Deformable and Wearable Strain Sensors

Highly conductive and stretchable fibers are crucial components of wearable electronics systems. Excellent electrical conductivity, stretchability, and wearability are required from such fibers. Existing technologies still display limited performances in these design requirements. Here, achieving highly stretchable and sensitive strain sensors by using a coaxial structure, prepared via coaxial wet spinning of thermoplastic elastomer‐wrapped carbon nanotube fibers, is proposed. The sensors attain high sensitivity (with a gauge factor of 425 at 100% strain), high stretchability, and high linearity. They are also reproducible and durable. Their use as safe sensing components on deformable cable, expandable surfaces, and wearable textiles is demonstrated.