Manipulation and patterning of carbon nanotubes utilizing optically induced dielectrophoretic forces

This study reports an optically driven platform upon which the manipulation and patterning of carbon nanotubes (CNTs) can be accomplished. A photoconductive layer made of amorphous silicon generates a nonuniform electric field within the developed platform at specific optically illuminated sites, which are usually referred to as “virtual electrodes,” that induces dielectrophoretic forces for manipulating the CNTs. The software-controlled light patterns enable a variety of flexible manipulation modes since it is now possible to dynamically reconfigure the optically projected electrode patterns. This approach allows for real-time manipulation and miscellaneous patterning of CNTs. The sorting and separation of bundled and dispersed CNTs is also demonstrated. This developed platform may be promising for rapid fabrication of CNT-based nanosensors together with nanoelectronics, purification as well as classification of synthesized CNTs and other applications requiring nanoscale manipulation.     

Optical bounce in a multi-domain vertical aligned liquid crystal display

Optical bounce phenomenon often occurs in a multi-domain vertical aligned (MVA) mode liquid crystal display (LCD). It results in the double image edge and motion image blur of the LCD. We find that the optical bounce phenomenon is due to nowadays overdriving method. Some suitable change of the method may eliminate the optical bounce phenomenon.     

Broadcom mediaDSP: A Platform for Building Programmable Multicore Video Processors

Broadcom's mediaDSP technology is a modular and scalable multiprocessor platform that provides the framework for building customized and programmable multicore processors for the video and image processing domain. The mediaDSP platform exploits task-level parallelism and includes architectural elements that support a task-based programming model. Broadcom's BCM35421 processor leverages mediaDSP technology to realize a single-chip, full high definition (FHD) frame rate converter for today's 120 Hz LCD TV sets.     

Operational Regimes and Physics Present in Optoelectronic Tweezers

Optoelectronic tweezers (OET) are a powerful light-based technique for the manipulation of micro- and nanoscopic particles. In addition to an optically patterned dielectrophoresis (DEP) force, other light-induced electrokinetic and thermal effects occur in the OET device. In this paper, we present a comprehensive theoretical and experimental investigation of various fluidic, optical, and electrical effects present during OET operation. These effects include DEP, light-induced ac electroosmosis, electrothermal flow, and buoyancy-driven flow. We present finite-element modeling of these effects to establish the dominant mode for a given set of device parameters and bias conditions. These results are confirmed experimentally and present a comprehensive outline of the operational regimes of the OET device.     

Electrical models of TFT‐LCD panels for circuit simulations

Abstract— As thin‐film‐transistor liquid‐crystal‐display (TFT‐LCD) panels become larger and provide higher resolution, the propagation delay of the row and column lines, the voltage modulation of Vcom, and the response time of the liquid crystal affect the display images now more than in the past. It is more important to understand the electrical characteristics of TFT‐LCD panels these days. There are several commercial products that simulate the electrical and optical performance of TFT‐LCDs. Most of the simulators are made for panel designers. However, this research is for circuit, system, and panel designers. It is made in a SPICE and Cadence environment as a commercial circuit‐design tool. For circuit and system designers, it will help to design the circuit around a new driving method. Also, it can be easily modified for every situation. It also gives panel designers design concepts. This paper describes the electrical model of a 15‐in. XGA (1024 × 768) TFT‐LCD panel. The parasitic resistance and capacitance of the panel are obtained by 3‐D simulation of a subpixel. The accuracy of these data is verified by the measured values of an actual panel. The developed panel simulation platform, the equivalent circuit of a 1 5‐in. XGA panel, is simulated by HSPICE. The results of simulation are compared with those of experiment, according to changing the width of the OE signal. The proposed simulation platform for modeling TFT‐LCD panels can be especially applied to large‐sized LCD TVs. It can help panel and circuit designers to verify their ideas without making actual panels and circuits.     

Dynamic Cell and Microparticle Control via Optoelectronic Tweezers

This paper reports on cell and microparticle manipulation using optically induced dielectrophoresis. Our novel optoelectronic tweezers (OET) device enables optically controlled trapping, transportation, and sorting via dielectrophoretic forces. By integrating a spatial light modulator and using direct imaging, arbitrary dynamic manipulation patterns are obtained. Here, we demonstrate manipulation functions, including particle collectors, single-particle traps, individually addressable single-particle arrays, light-defined particle channels, and size-based particle sorting. OET-induced particle manipulation velocities are analyzed as a function of the applied voltage, optical pattern linewidth, and single-particle trap dimensions.     

Diagnostic techniques for the dynamics of a thin liquid film under forced flow and evaporating conditions

Motivated by quantification of micro-hydrodynamics of a thin liquid film which is present in industrial processes, such as spray cooling, heating (e.g., boiling with the macrolayer and the microlayer), coating, cleaning, and lubrication, we use micro-conductive probes and confocal optical sensors to measure the thickness and dynamic characteristics of a liquid film on a silicon wafer surface with or without heating. The simultaneous measurement on the same liquid film shows that the two techniques are in a good agreement with respect to accuracy, but the optical sensors have a much higher acquisition rate up to 30 kHz which is more suitable for rapid process. The optical sensors are therefore used to measure the instantaneous film thickness in an isothermal flow over a silicon wafer, obtaining the film thickness profile and the interfacial wave. The dynamic thickness of an evaporating film on a horizontal silicon wafer surface is also recorded by the optical sensor for the first time. The results indicate that the critical thickness initiating film instability on the silicon wafer is around 84 μm at heat flux of ~56 kW/m². In general, the tests performed show that the confocal optical sensor is capable of measuring liquid film dynamics at various conditions, while the micro-conductive probe can be used to calibrate the optical sensor by simultaneous measurement of a film under quasi-steady state. The micro-experimental methods provide the solid platform for further investigation of the liquid film dynamics affected by physicochemical properties of the liquid and surfaces as well as thermal-hydraulic conditions.     

Electromechanical characterization of a new micro programmable blazed grating by laser Doppler vibrometry

The prototype of a new micro programmable blazed grating driven electrostatically was fabricated using a two-layer polysilicon surface micromachining process. And initially, to characterize its electromechanical performances, such as the driving voltage versus displacement relationship, frequency response and step response, the laser Doppler vibrometry was employed. The measured results reveal the pull-in voltage of 110–115 V, resonant frequency of 78 KHz, quality factor of 2.89, adjusting time of 12 μs, and damping ratio of ~0.68 for the achieved grating sample. As a result, the grating functions well electromechanically. As for its optical performances, a number of optical experiments are in progress.     

Measuring and modeling per‐element angular visibility in multi‐view displays

Abstract— Multi‐view displays employ an optical layer which distributes the light of an underlying TFT‐LCD panel in different directions. Certain properties of the layer create specific artifacts, such as ghost images, moiré patterns, and masking. The layer was modeled as an image‐processing channel, and the display parameters related with the model were identified, which are importantfor the design of image‐processing algorithms for artifact mitigation. The identified parameters are interleaving pattern, angular visibility, and frequency throughput of the display. A methodology for deriving these parameters for an arbitrary LCD‐based multi‐view display are presented, which does not require precisely positioned measurement equipment. As a case study, measurement and modeling results for a particular multi‐view display are also presented.     

Ultra‐narrow border display with a cover glass using liquid crystal displays with a polyimide substrate

Plastic liquid crystal displays (LCDs) termed sheet LCDs with transparent polyimide (PI) substrates were constructed. There is a lot of potential to expand the use of these LCDs in LCD applications. Herein, we investigated a structure for sheet LCDs such as high‐density main post spacers (PSs) and PI substrates with the aid of a barrier layer to control the residual stress and protect the liquid crystal from moisture. Drawing on this, we propose an ultra‐narrow border LCD that makes of the developed sheet LCDs. The most significant improvement is that the four borders of the LCD can be folded to wrap the backlight unit. This LCD was based on various new techniques, including the use of plastic substrates, processing of polarizer films, control of the neutral surface of a bending component based on the sealant width, and the use of a cover glass with a lens effect. We believe that these novel LCDs will be useful in numerous new applications.     

Review of various measurement methodologies of migration ion influence on LCD image quality and new measurement proposal beyond LCD materials

Nowadays, thin‐film transistor liquid crystal displays (TFT‐LCDs) have realized high reliability of display characteristics by improving liquid crystal (LC) materials and cell fabrication processes. In order to improve display reliability, measurement methodologies are important to see the progress of improvement of materials and processes; thus, our group has proposed voltage holding ratio (VHR), ion impurity, residual direct current (DC) and elastic constants for LC cells, and the optical anisotropy of an alignment layer on indium tin oxide (ITO) glass substrate for LCD industry. In case of an ion impurity, we have succeeded in measuring the ion impurity amount in TFT‐LCD. Furthermore, we have recently proposed ion impurity measurement methodology for beyond LCD applications that are organic light emitting diode (OLED) and organic photovoltaics (OPV). In this review, I introduce each measurement methodology for LCDs and beyond LCDs in detail.     

基于中间层监督卷积神经网络的图像超分辨率重建

目的 基于学习的图像超分辨率重建方法已成为近年来图像超分辨率重建研究的热点。针对基于卷积神经网络的图像超分辨率重建（SRCNN）方法网络层少、感受野小、泛化能力差等缺陷,提出了基于中间层监督卷积神经网络的图像超分辨率重建方法,以进一步提高图像重建的质量。方法 设计了具有中间层监督的卷积神经网络结构,该网络共有16层卷积层,其中第7层为中间监督层;定义了监督层误差函数和重建误差函数,用于改善深层卷积神经网络梯度消失现象。训练网络时包括图像预处理、特征提取和图像重建3个步骤,采用不同尺度因子（2、3、4）模糊的低分辨率图像交叉训练网络,以适应对不同模糊程度的图像重建;使用卷积操作提取图像特征时将参数pad设置为1,提高了对图像和特征图的边缘信息利用;利用残差学习完成高分辨率图像重建。结果 在Set5和Set14数据集上进行了实验,并和双三次插值、A+、SelfEx和SRCNN等方法的结果进行比较。在主观视觉评价方面,本文方法重建图像的清晰度和边缘锐度更好。客观评价方面,本文方法的峰值信噪比（PSNR）平均分别提高了2.26 dB、0.28 dB、0.28 dB和0.15 dB,使用训练好的网络模型重建图像耗用的时间不及SRCNN方法的一半。结论 实验结果表明,本文方法获得了更好的主观视觉评价和客观量化评价,提升了图像超分辨率重建质量,泛化能力好,而且图像重建过程耗时更短,可用于自然场景图像的超分辨率重建。     

An introduction to PSS‐LCDs: A fast‐optical‐response smectic LCD

Abstract— A new type of fast‐optical‐response liquid‐crystal display is introduced. This display uses a certain type of smectic liquid‐crystal material that has a fast optical response as well as a native wide viewing angle. Unlike well‐known smectic‐based LCD technologies, this new type of LCD technology is highly compatibile with most nematic‐based LCDs. This compatibility provides advantages for practical uses. Here, the initial molecular alignment and drive concept as well as the general performance of this new display technology are discussed.     

An Interconnect Strategy for a Heterogeneous, Reconfigurable SoC

Editor's note:The diversification of the SoC market has increased the need for domain-specific programmable platforms that can be tailored to postfabrication products. This article presents a design case study on the interconnect for such a programmable platform, as part of the Morpheus project.—Li-Shiuan Peh, Princeton University     

Fabrication of ultraviolet photoconductive sensor using a novel aluminium-doped zinc oxide nanorod-nanoflake network thin film prepared via ultrasonic-assisted sol-gel and immersion methods

Unique and novel thin films with aluminium (Al)-doped zinc oxide (ZnO) nanostructures consisting of nanorod-nanoflake networks were prepared for metal-semiconductor-metal (MSM)-type ultraviolet (UV) photoconductive sensor applications. These nanostructures were grown on a glass substrate coated with a seed layer using a combination of ultrasonic-assisted sol-gel and immersion methods. The synthesised ZnO nanorods had diameters varying from 10 to 40 nm. Very thin nanoflake structures were grown vertically and horizontally on top of the nanorod array. The thin film had good ZnO crystallinity with a root mean square roughness of approximately 13.59 nm. The photocurrent properties for the Al-doped ZnO nanorod-nanoflake thin films were more than 1.5 times greater than those of the seed layer when the sensor was illuminated with 365 nm UV light at a density of 5 mA/cm². The responsivity of the device was found to be dependent on the bias voltage. We found that similar photocurrent curves were produced over eight cycles, which indicated that the UV sensing capability of the fabricated sensor was highly reproducible. Our results provide a new approach for utilising the novel structure of Al-doped ZnO thin films with a nanorod-nanoflake network for UV sensor applications. To the best of our knowledge, UV photoconductive sensors using Al-doped ZnO thin films with a nanorod-nanoflake network have not yet been reported.     

Novel WV film for wide‐viewing‐angle TN‐mode LCDs

Abstract— A new optical compensation film refered to as WV‐EA film for TN‐mode TFT‐LCDs has been developed, resulting in higher contrast ratio, wider‐viewing‐angle characteristics, and improved color shift than their predecessors, especially in the horizontal direction. These features of the new WV film were achieved as a result of haze reduction and optimizing the optical characteristics of the polymerized discotic material layer and TAC film. These features are suitable for large‐sized and wide‐aspect‐ratio LCD monitors and TVs.     

Curved vertical‐alignment liquid crystal display with uniform brightness: From pixel design to verification

Curved liquid crystal display (LCD) suffers from an issue of uneven brightness among the vertical‐alignment LCD panels based on thin glass substrates. In this work, we investigated its origin through optical simulation and successfully realized uniform brilliance for 27‐inch curved LCD panels. The optical simulation revealed that the dark areas on the bending sides of the curved LCD panel originated from the reduced azimuth angle of the liquid crystals (LC) next to the ITO trunk. This issue could be resolved by decreasing the pretilt angle of the LC on the color filter side. Through developing pretilt angle tuning technologies, we experimentally verified that the uniform brilliance could be achieved for 27‐inch curved LCD panels with 900‐mm curvature on thin glass substrates.     

基于嵌入式的人脸图像采集显示系统的制作

针对目前嵌入式开发平台上视频显示不流畅的现象,文中提出通过USB 摄像头采集人脸图像的方案。该方 案是基于三星S5PV210 处理器和嵌入式Linux 操作系统,并在其移植了Qt 和OpenCv。文章介绍了以USB 摄像头为视频图像 采集设备,通过OpenCv 进行视频图像采集的过程,以及通过Qt 实现人脸图像实时显示在LCD 屏上的过程,经测试图像能够 在LCD 屏上流畅显示,为实时在嵌入式平台上流畅显示视频图像提供了方案。     

A cube to learn: a tangible user interface for the design of a learning appliance

In this paper we introduce the design and development of the Learning Cube as a novel tangible learning appliance. Using the common shape of a cube we implemented a general learning platform that supports test based quizzes where questions and answers can be text or image based. Exploiting the physical affordances of the cube and augmenting it with embedded sensors and LCD displays placed on each face, we present different learning appliances as playful learning interfaces for children. Based on the initial observations of the experience with children, we argue that breaking conventions about how a computer has to look like, and providing children with a playful interface is a promising approach to embed and integrate technology into children’s everyday context and activities.     

LCD applications of thin‐crystal‐film polarizers

Abstract— We have developed a new technique for the production of thin crystal film (TCF) by deposition, molecular alignment, and the drying of water‐based lyotropic‐liquid‐crystal (LLC) materials. TCF exhibits high optical anisotropy and birefringence. This paper presents liquid‐crystal‐display (LCD) applications and opportunities for TCF plastic sheet polarizers, retarders, and color‐correction films as well as LCD designs with TCF internal polarizers.