Flexible Quantum Dot Light-Emitting Diodes for Next-Generation Displays
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会议详细议程(Final Program)
会议详细议程(Final Program) 2019 International Conference on Display Technology March 26th—29th, 2019 (Tuesday - Friday) Kunshan International Convention and Exhibition Center Kunshan, Suzhou, China Plenary Session Wednesday, Mar. 27/14:00—18:00/Reception Hall Chair: Shintson Wu (吴诗聪), University of Central Florida (UCF) Title: Laser display Technology (14:00-14:30) Zuyan Xu (许祖彦), Technical Institute of Physics and Chemistry, China Academy of Engineering (CAE) Title: Thin film transistor technology and applications (14:30-15:00) Ming Liu (刘明), Institute of Microelectronics of the Chinese Academy of Sciences Title: Technology creates a win-win future (15:00-15:30) Wenbao Gao (高文宝), BOE Title: Gallium nitride micro-LEDs: a novel multi-mode, high-brightness and fast-response display technology (15:30-16:00) Martin Dawson, the University of Strathclyde’s Institute of Photonics, the Fraunhofer Centre for Applied Photonics Title: Virtual and Augmented Reality: Hope or Hype? (16:00-16:30) Achin Bhowmik, Starkey Hearing Technologies Title: Monocular Vision Impact: Monocular 3D and AR Display and Depth Detection with Monocular Camera (16:30-17:00) Haruhiko Okumura, Media AI Lab, Toshiba Title: ePaper, The Most Suitable Display Technology in AIoT (17:00-17:30) Fu-Jen (Frank) Ko, E Ink Holdings Inc. Title: Application Advantage of Laser Display in TV Market and Progress of Hisense (17:30- 18:00) Weidong Liu (刘卫东), Hisense Thursday, Mar. 28/8:30—12:30/Reception Hall Chair: Hoi S. Kwok (郭海成), Hong Kong University of Science and Technology Title: High Performance Tungsten-TADF OLED Emitters (8:30-9:00) Chi-Ming CHE (支志明), The University of Hong Kong Title: Challenges of TFT Technology for AMOLED Display (9:00-9:30) Junfeng Li (李俊峰), Nanyang Technological University, Innovation Research Institute of Visionox Technology Co., Ltd. -
The Parylene Deposition Process
History of Parylene Parylene development started in 1947, when Michael Szwarc discovered the polymer as one of the thermal decomposition products of a common solvent p-xylene at temperatures exceeding 1000 °C. Szwarc first postulated the monomer to be para-xylylene which he confirmed by reacting the vapors with iodine and observing the para-xylylene di-iodide as the only product. The reaction yield was only a few percent, and a more efficient route was found later by William F. Gorham at Union Carbide. The Parylene Deposition Process Parylene coating is applied through a vapor deposition process onto the substrate or material that is being coated. Depending on the coating type and required thickness, typical parylene deposition rates are about .2/mils per hour, so machine runs can vary from as little as 1 hour to over 24 hours. The process begins with raw dimer in solid state (these are: Parylene C, Parylene N, Parylene D, Parylene AF-4, or other variants) being placed into a loading boat, which is then inserted into the vaporizer. The raw dimer is heated between 100-150º C. At this time, the vapor is pulled, under vacuum into the furnace and heated to very high temperatures which allows for sublimation and the splitting of the molecule into a monomer. The monomer gas continues to be drawn by vacuum one molecule at a time onto the desired substrate at ambient temperatures in the coating chamber. The final stage of the parylene deposition process is the cold trap. The cold trap is cooled to between -90º and -120º C and is responsible for removing all residual parylene materials pulled through the coating chamber. -
UV Cured Flexible Cholesteric Liquid Crystal Displays
UV Cured Flexible Cholesteric Liquid Crystal Displays Tod Schneider, Erica Montbach, Don Davis, Sean Franklin, Diaz McDaniel, Mark Lightfoot, Nithya Venkataraman, Forrest Nicholson, Asad Khan, and J. William Doane Kent Displays, Inc. Kent, OH, USA Abstract Flexible Cholesteric liquid crystal displays have been rapidly maturing into a strong contender in the flexible display market. Encapsulation of the Cholesteric liquid crystal permits the use of flexible plastic substrates and roll-to-roll production. Recent advances include ultra-thin displays, laser-cut segmented displays of variable geometry, and smart card applications. Exciting technologies such as UV curing, and simultaneous laser-edge sealing/singulation enable high volume production, excellent quality control and non-traditional display geometries and formats. Keywords: UV Cure, Flexible Displays, Roll-to-Roll, Plastic Substrates, Cholesteric Liquid Crystals, Bistable Introduction Nearly every commercial liquid crystal display (LCD) manufactured and sold today is made from a sandwich of liquid crystal (LC) between two precisely spaced glass substrates coated with a transparent conductor. A few challenges remain for LCDs in the consumer market; namely, flexibility, durability, weight and power consumption. The first three issues can be addressed by using thin plastic substrates whereas the last issue can be solved using a bistable display, i.e. a display that is stable (with no power applied) in two states such as reflective or transmissive. Unfortunately, a problem arises when sandwiching liquid crystal between two flexible substrates: the fluid will flow! When the cell is flexed or pressed upon, the gap between the substrates becomes smaller displacing the LC and inducing flow. Cholesteric liquid crystal displays (ChLCDs) are bistable LCDs that have low power consumption and exhibit high reflectance under ambient lighting1. -
Feature Article: Will Quantum Dots Make for a Brighter Future?
Renishaw plc T +44 (0)1453 524524 New Mills, Wotton-under-Edge, F +44 (0)1453 524901 Gloucestershire, GL12 8JR E [email protected] United Kingdom www.renishaw.com Feature article Will quantum dots make for a brighter future? First discovered in 1980, colloidal semiconductor lighting component market will surpass US$ 2 billion by the nanocrystals or quantum dots (QDs) are typically between end of 2016 and reach US$ 10.6 billion by 2025. 2 - 10 nanometres (nm) in diameter and are now being QD-backlit LCDs and QLEDs commercialised with possible applications in a variety of thin film devices including solar cells, photodetectors and The most immediate applications for QDs are in LCD LEDs. QDs have profound implications for the flat panel backlighting applications (LED TVs). QDs have been display (FPD) industry, but is it really a case of all change incorporated into a filter film designed to be inter-leaved from here on in? between the LED backlight unit and LCD panel. Current LCD backlights use white LEDs, which are blue LEDs coated with a One of the many advantages of QDs is their colour tunability phosphor layer - making them rather inefficient. The quantum resulting from a quantum mechanical effect known as dot filter allows the use of pure blue LEDs in the backlight as ‘confinement’. Quantum dots are also both photo- and it converts some of the incident blue light, by absorption and electro-luminescent as a result of their material composition, re-emission, into very pure green and red. As a result, the LCD which may include Cadmium Selenide (CdSe) and Zinc panel receives a richer white light which expands the range Sulphide (ZnS). -
Lens Array by Electrostatic Patterning of Dielectric Microspheres in a Parylene-C Well Template H
LENS ARRAY BY ELECTROSTATIC PATTERNING OF DIELECTRIC MICROSPHERES IN A PARYLENE-C WELL TEMPLATE H. Yang*, M. Cornaglia and Martin A. M. Gijs Laboratory of Microsystems, École Polytechnique Fédérale de Lausanne, Switzerland ABSTRACT We present the fabrication of a microlens array which can be integrated into a microfluidic device. In the demonstrated technique, a microwell array is firstly fabricated in a Parylene-C layer by a standard cleanroom process. Afterwards, the optically transparent dielectric microspheres with high refractive index are patterned inside the well template by utilizing an electrostatic technique. The mechanism of microsphere patterning is studied, and the lens effect of the microsphere is experimentally verified in a water-based medium. We also present a detailed two-dimensional numerical optical simulation study on the patterned microspheres using the Finite Element Method (FEM). KEYWORDS: Microlens array, Dielectric microspheres, Microfabrication, Parylene-C INTRODUCTION Microlenses that are integrated on microfluidic chips enable several important optical features, such as profiting from a large local numerical aperture (NA) and high light collection efficiency, so that, for example, the optical read-out in an immunoassay is facilitated and the detection limit decreased [1]. Optically transparent microspheres with high refractive index act as ball lenses and show strong capability in focusing light. Using microspheres to build a compact system integrated with microfluidics inevitably will be of benefit to the field of life sciences, diagnostics or environmental monitoring. In this study, an electrostatic technique for fabrication of a microlens array by printing single dielectric microspheres into a patterned microwell template is proposed. The immobilized microspheres can focus the illumination, such as the optical signal originating from the presence of fluorescent markers beneath a microlens, into a very narrow region with high optical intensity, which is also known as a ‘photonic nanojet’ [2]. -
Quantum Dot Displays to Spur Premium Display Market Growth
Publication date: 09 Dec 2019 Author: Richard Son Principal Analyst, Display Chemical Materials [Display Dynamics] Quantum dot displays to spur premium display market growth Brought to you by Informa Tech [Display Dynamics] Quantum dot displays to 1 spur premium display market growth Table of Figures: michellewhitcombihsmarkitcom_2019_12_9_11_5_32_capturejpg1 ..............................................3 michellewhitcombihsmarkitcom_2019_12_9_11_6_23_capturejpg2 ..............................................3 © 2020 Omdia. All rights reserved. Unauthorized reproduction prohibited. [Display Dynamics] Quantum dot displays to 2 spur premium display market growth Key findings . Resolution, slim and bezel-less designs, and a wide color gamut are barometers of innovation in display technology as well as key marketing points of different display products. After the introduction of organic light-emitting diode (OLED), quantum dot (QD), and microLED display technologies that guarantee high definition and flexibility in design, a wide color gamut is now the key feature that determines the premium value of a display. QD displays, groomed to be the core display technology for Samsung Electronics and Samsung Display, are expected to boost the growth of the premium display market. Market for premium displays with various advanced features set to steadily grow Ever since the start of the digital display era, display size, design, and resolution have been used as barometers of innovation in display technology. Display makers marketed size and design as their distinctive features to lure consumers. To make a display slimmer, light-emitting diode backlight unit liquid-crystal displays (LED BLU LCDs) widely adopted edge BLU and bezel-less designs. Curved and bendable display technologies that enabled the production of super-large sized and flexible display designs also gained consumers’ attentions. -
00098OFC2.Qxp:SID Cover
FLEXIBLE AND LOW-POWER DEVICES February 2010 Official Monthly Publication of the Society for Information Display • www.informationdisplay.org Vol. 26, No. 2 FEBRUARY 2010 Information VOL. 26, NO. 2 COVER: This flexible display module from Plastic Logic was made with plastic electronics and Vizplex display media provided by E Ink Corp. It has a resolution of 1280 × 960 and 150 ppi. Cover image courtesy of Plastic Logic Limited, DISPLAY 2009. 2 Editorial Now More than Ever Before: Flexible and Low-Power Technology Meets A Need Stephen P. Atwood 3 Industry News Prime View International, HYDIS Technologies, and LG Display Announce Comprehensive Cooperation Agreement Jenny Donelan 4 Guest Editorial A New Breed of Display Starts to Flex Its Muscles Robert Zehner 6 President’s Corner Getting Excited about Seattle Paul Drzaic 8 Frontline Technology: Flexible AMOLEDs for Low-Power, Rugged Applications Flexible AMOLEDs equipped with phosphorescent OLEDs are well-positioned for low-power, rugged, full-color video applications. Replacing glass with flexible substrates and thin-film encap- sulation makes displays thinner, lighter, and non-breakable – all attractive features for portable applications. With enhanced flexibility and low power consumption, a range of revolutionary opportunities are being created. CREDIT: Cover design by Acapella Studios, Inc. Ruiqing Ma, Mike Hack, and Julie J. Brown 16 Frontline Technology: Flexible Displays Made with Plastic Electronics Plastic Logic has designed and constructed a full-scale manufacturing facility for flexible display modules fabricated using organic semiconductors (“plastic electronics”). These display modules are lightweight, flexible, and robust and are used in the QUEproReader, an e-reader device for mobile business professionals that was introduced in January 2010. -
Formation of Three-Dimensional Parylene C Structures Via Thermoforming
Journal of Micromechanics and Microengineering J. Micromech. Microeng. 24 (2014) 065003 (9pp) doi:10.1088/0960-1317/24/6/065003 Formation of three-dimensional Parylene C structures via thermoforming BJKim1, B Chen2,MGupta2 and E Meng1,3 1 Department of Biomedical Engineering, University of Southern California, 1042 Downey Way, DRB-140, Los Angeles, CA 90089-1111, USA 2 Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089-1211, USA 3 Ming Hsieh Department of Electrical Engineering, University of Southern California, 3740 McClintock Ave., EEB-100, Los Angeles, CA 90089-2560, USA E-mail: [email protected] Received 14 January 2014, revised 19 March 2014 Accepted for publication 31 March 2014 Published 25 April 2014 Abstract The thermoplastic nature of Parylene C is leveraged to enable the formation of three-dimensional structures using a thermal forming (thermoforming) technique. Thermoforming involves the heating of Parylene films above its glass transition temperature while they are physically confined in the final desired conformation. Micro and macro scale three-dimensional structures composed of Parylene thin films were developed using the thermoforming process, and the resulting chemical and mechanical changes to the films were characterized. No large changes to the surface and bulk chemistries of the polymer were observed following the thermoforming process conducted in vacuum. Heat treated structures exhibited increased stiffness by a maximum of 37% depending on the treatment temperature, due to an increase in crystallinity of the Parylene polymer. This study revealed important property changes resulting from the process, namely (1) the development of high strains in thermoformed areas of small radii of curvature (30–90 µm) and (2) 1.5% bulk material shrinkage in thermoformed multilayered Parylene–Parylene and Parylene–metal–Parylene∼ films. -
Study on the Surface Characteristics of Parylene-C Films in Inductively Coupled O2/CF4 Gas Plasma
P2-44 / Y. -H. Ham Study on the surface characteristics of parylene-C films in inductively coupled O2/CF4 gas plasma Yong-hyun Ham1, Kyu-Ha Baek1, Kun-Sik Park1, Hong-sik Shin1, Ho-jin Yun1, Kwang-Ho Kwon2 , and Lee-Mi Do1 1 Electronics and Telecommunications Research Institute (ETRI), 138 Gajeongdong, Yuseong-gu, Daejeon 305-700, Korea Tel.:82-2-860-5776, E-mail: [email protected] 2 Dept. Control and Instrumentation Engineering, Korea University, Jochiwon-eup, Yeongi-gun, chungnam 339-700, Korea Keywords: Parylene-C, O2/CF4, Plasma treatment, ICP Abstract surface.[4] As a result, functional groups lead to In this article, we reported the results of etching poly- degradation of transistor performance. Hence, monochloro-para-xylylene (parylene-C) thin films using preventing the functional groups is essential to inductively coupled plasma and CF4/O2 gas mixture. The improve the OTFTs’ performance. Research in this CF4 gas fraction increased up to the approximately 16 %, field has been so far studied by many researching the polymer etch rate increased in the range of 277 – 373 groups. However, various gas chemistries have not nm/min. It confirmed that the etch rate of the parylene-C been widely examined to reduce the formation of the mainly depended on the O radical density in the plasma. Using a contact angle measurement, the contact angle functional groups, even though the reaction of the polymer with the plasma-created species makes a increased with increasing the CF4 fraction. Moreover, the contact angle was highly related a CFx functional group on large effect on the formation of the functional groups. -
Various Display Technologiess
VARIOUS DISPLAY TECHNOLOGIESS Mr. Virat C. Gandhi1 1Computer Department, C. U. Shah Technical Institute of Diploma Studies Abstract—A lot has been invented from the past till now in regards with the display technologies. It gives an immense life to electronic device when good display technology are being used. Now a days displays are coming in various sizes for different portable devices like smart phones, tablets, smart watch, televisions, laptops etc. People are expecting better display no matter what device they use. In this paper I have given an overview of some of the past technologies to the technologies till now. Flat-panel displays use Liquid-crystal display (LCD) technology to make them much lighter and thinner when compared with a traditional monitor. A liquid crystal display consists of an array of tiny segments (called pixels) that can be manipulated to present information. Plasma panels, also called gas discharge displays, are constructed by filling the region between two glass plates with a mixture of gases that usually include neon. In LED, A matrix of diodes is arranged to form the pixel positions in the display, and picture definition is stored in refresh buffer. OLED (Organic Light Emitting Diode) technology relies on the organic materials. Keywords— Display Technology; LCD; LED; Flexible display; Curved display; I. INTRODUCTION In today’s smart world, people are carrying smart devices all over the places they visit. Wherever people are they are surrounded or accompanied by display devices, such as smart phones, tablets, notebooks and advertising screens. Different devices uses different display technologies to enrich devices facilities. -
Flexible Display Patent Landscape and Implications from the America Invents Act
Flexible Display Patent Landscape and Implications From the America Invents Act Donald J. Featherstone,* Raymond J. Werner,** Christian A. Camarce,*** and Susan E. Cullen**** Abstract Developments in flexible display technology are expected to create significant new market opportunities for consumer electronic and commercial products. The potential economic impact of these new products is evidenced by the rapid growth around the world in patent application filings directed to flexible display technology areas. At the same time, changes to U.S. patent law, practice, and strategies have been triggered by the enactment of the Smith-Leahy America Invents Act. This article describes the patent landscape for flexible displays and ways in which newly enacted changes in patent law can facilitate the development of flexible display patent portfolios. I. Overview of the Flexible Patent Display Landscape. a. What Are Flexible Displays? Flexible displays are displays that can be bent, rolled, folded and/or twisted in many different configurations. As early as the 1970s, flexible display technology was used in e-paper displays, which were used to mimic the pliant properties of paper but with the capacity to display digital images.1 Today, largely led by Asian companies, research and development has moved past early e- paper display technology and has rapidly evolved into new materials, manufacturing methods, control means and integration schemes. Today’s applications of flexible displays are predominately in consumer electronic products such as mobile devices, TV screens, and similar video and multimedia products. * Donald J. Featherstone is a Director at Washington DC-based intellectual property specialty law firm Sterne, Kessler, Goldstein & Fox P.L.L.C. -
Quantum Dots for Wide Color Gamut Displays from Photoluminescence
Kang et al. Nanoscale Research Letters (2017) 12:154 DOI 10.1186/s11671-017-1907-1 NANO EXPRESS Open Access Quantum Dots for Wide Color Gamut Displays from Photoluminescence to Electroluminescence Yongyin Kang1, Zhicheng Song2*, Xiaofang Jiang1, Xia Yin1, Long Fang1, Jing Gao1, Yehua Su1 and Fei Zhao1* Abstract Monodisperse quantum dots (QDs) were prepared by low-temperature process. The remarkable narrow emission peak of the QDs helps the liquid crystal displays (LCD) and electroluminescence displays (QD light-emitting diode, QLED) to generate wide color gamut performance. The range of the color gamut for QD light-converting device (QLCD) is controlled by both the QDs and color filters (CFs) in LCD, and for QLED, the optimized color gamut is dominated by QD materials. Keywords: Quantum dots (QDs), Quantum dot light-converting device (QLCD), Color filter (CF), Quantum dot light-emitting diode (QLED), Wide color gamut, Solution process Background ways to produce white light using LEDs, and the color Colloidal quantum dots (QDs) have been actively pursued gamut is determined by the contour of the emission for both fundamental research and industrial development peak from the phosphors. The conventional method uses due to their solution processibility and size-dependent a blue LED chip with YAG (yttrium-aluminum-garnet)- optical properties associated with quantum confinement based phosphor directly packaged on its top, the color [1–4]. The most promising application of QDs is as emit- gamut is typically ~72% NTSC (National Television ters in biomedical labeling, solid-state lighting, and display Standards Committee). Advanced phosphor-based tech- [5–7]. For instance, in 2009, the US Department of Energy nologies replace the YAG by green phosphors and the (DOE) highlighted a high-performance solid-state lighting red phosphors, namely RG phosphor solution.