Symposium Preview

Plan your visit to Display Week 2010 with an advance look at some of the most exciting developments that will be revealed in the symposium's extensive collection of display-technology sessions.

by Jenny Donelan

IT IS NEVER EASY to choose the papers that will be presented at the Society for Information Display's annual Symposium at Display Week. Nevertheless, the 13 sub-committees have done their work: this May, in Seattle, cutting-edge research, ingenious manufacturing ideas, and brilliant solutions to ongoing design problems will all be disclosed by top researchers as they share their results with the rest of the international electronic-display community at Display Week 2010.

The following is a list of session highlights by subcommittee, which includes active-matrix devices, applications, applied vision, display electronics, display manufacturing, display measurement, display systems, emissive displays, field-emission displays, flexible displays, liquid-crystal technology, OLEDs, and projection. In addition to the session topics listed here, the Society for Information Display has also designated special topics of interest for Display Week 2010. These include touch technology, green technology, 3-D, and solid-state lighting. For more on touch and green technology, see the First Look articles in the March 2010 issue of Information Display magazine. First Look pieces on 3-D and solid-state lighting appear in this issue.

Active-Matrix Devices: Momentum Builds for Oxide Conductors

The most exciting trend to surface in last year's active-matrix submissions was the use of oxide-semiconductor technology as a replacement for silicon-semiconductor technology. In fact, this very section began last year with the question: "Can oxide thin films substitute for silicon?" Based on this year's papers, the answer would seem to be "yes," according to subcommittee chair Roger Stewart, President, Sourland Mountain Associates.

"Everything seems to be moving toward tin-oxide," he says, citing several submissions as evidence, but, in particular, "Highly Reliable Oxide-Semiconductor TFT for AMOLED Displays," by Toshiaki Arai of Sony. "Sony has made the transistors better than anything we've seen before," he says, "and they've taken it all the way into production and made displays with it. There is huge potential here." That potential, he explains, includes cheaper manufacturing costs and lower power consumption. Other papers to watch for in this area include "Amorphous Oxide TFT Backplanes for Large-Sized AMOLED TVs," by Yeon Gon Mo of Samsung Mobile Display, and "Low-Power LCD Using In-Ga-Zn-Oxide TFTs Based on Variable Frame Frequency," by Seiko Amamo of the Semiconductor Energy Laboratory Co., Ltd. Other papers of interest include "A System LCD with Optical Input Function Using IR Backlight Subtraction Scheme," by Kohei Tanaka of Sharp, which describes a new type of low-power-consumption touch screen that uses an infrared backlight subtraction scheme suitable for integration with mobile products. "A Novel Multi-Level Memory In-Pixel Technology for Ultra-Low-Power LTPS TFT-LCD," by Naoki Ueda of Sharp, explains how a high-image-quality low-power-consumption display can be devel-oped by incorporating memory into each pixel.

Applications: Digital Signage Evolves in Many New Directions

Applications are one of the most exciting areas of display technology – where all the research, planning, and hard work come together in the form of real products. This year, popular paper topics include 3-D, solid-state lighting, and digital signage. Many of the most interesting submissions feature digital signage, including "Technologies and Applications for Large-Sized High-Resolution Tiled-Display System," by Sachin Deshpande of Sharp Laboratories of America, which traces the development of the "SharpWall," a 177-in.-diagonal tiled prototype with a 10,000 x 4500-pixel resolution. Other signage papers include "Interactive and Natural View-ing of Giga-Pixel Images on Large-Sized Tiled Displays," by Chang Yuan of Sharp Labora-tories of America, which describes how on-screen images can be controlled by viewers' natural movements in front of the display, and Distinguished Paper "Ultra-Low-Reflective 60-in. LCD with Uniform Moth-Eye Surface for Digital Signage," by Tokio Taguchi of Sharp Corp. The anti-reflection surface described in Taguchi's paper incorporates nanostructures based on certain moths' corneal structures, which are covered by sub-wavelength anti-reflection structures.

Also recommended are "60-in. Highly Transparent See-Through Active-Matrix Display without Polarizers," by Eiji Satoh of Sharp Corp., which introduces an informationdisplay that can substitute for windows in stores and other venues, and "Large-Area Plasma-Panel Radiation Detectors for Nuclear Medicine Imaging to the Super-Large Hadron Collider," by Peter Friedman of Integrated Sensors LLC, which describes a new type of radiation sensor derived from PDP technology.

Applied Vision: Human Factors and Image Quality

Many of this year's most interesting Applied Vision papers focus on image quality and human factors. Among the former are the Invited Paper "Enhancing the Visible with the Invisible: Exploiting Near-Infrared to Advance Computational Photography and Computer Vision," by Sabine Susstrunk of the Swiss Federal Institute of Technology, and "Factors Affecting Image-Quality Preferences," by PremNandhini Satgunam of The Schepens Eye Research Institute at Harvard Medical School. Susstrunk's paper discusses the benefits of using near-infrared (NIR) radiation images in conjunction with standard color images for certain computational photog-raphy and computer-vision tasks such as material classification and skin smoothing. Satgunam's presentation reveals the reactions of human subjects asked to state preferences with regard to enhanced video imagery. Preferences for enhancement depended on the content, and particularly on the presence or absence of human faces.

The Applied Vision sessions also feature many 3-D and solid-state-lighting–related papers this year. Both 3-D and solid-state lighting have dedicated sessions in 2010, and some of the most important papers from those sessions are discussed in the First Look articles also in this issue.

An additional Invited Paper of note is "3-D Technology Development and the Human Factor Effect," by Chao-Yuan Chen of AU Optronics Corp., which examines the relationship among 3-D content, display hardware, and human factors.

Display Electronics: A Far-Ranging Support System

Last year, Display Electronics Chair Michiel A. Klompenhouwer remarked that a display had become so much more than just a panel – signal processing, interfaces, and driving technologies were just as important in terms of developing high-image-quality low-power slim-form-factor products. In 2010, this trend has continued, as demonstrated by display-electronics papers covering technologies ranging from LCDs to OLEDs to electronic paper and electronics in areas such as display drivers and interfaces, field sequencing, local dimming, and color management.

Among this year's sessions is one devoted to Multi-Primary Displays, with four papers, and one on Driving Electronic Paper, which includes the Invited Papers "Drive Systems for Electronic-Paper Displays," by Ian French of Prime View International, and "ID Document Technologies with Bendable AMOLED Displays," by Joerg Fischer of Bundesdruckerei GmbH.

Another paper of interest is "A Monolithic Block-Wise Functional Light Guide for 2-D Dimming LCD Backlight," by K. Käläntär of Nippon Leiz, which describes a functional light-guide plate (LGP) that uses recessed V-grooves as semi-partitions between consecutive blocks to realize a backlight unit for a 2-D dimming display. The height of a groove controls the cross-talk between the blocks.

Display Week 2010 at a Glance

Display Manufacturing: Green Is the "Third Wave"

Green is an extremely important part of this year's symposium (see "Display Week 2010: Green Technology" in the March 2010 issue), and nowhere is this more apparent than in the Display Manufacturing sessions. The Invited Papers "Green LCD Technologies," by Po-Lun Chen of AU Optronics Corp., and "EcoDesign for TV Displays," by Cornelis Teunissen of Philips Consumer Lifestyle, both contain vital information about efforts being made in this critical area of display technology. Chen's paper discusses three "waves" in LCD development. The first was performance; the second, cost-reduction; and the third, the greening of both product and manufacturing processes. Teunissen's paper looks at the eco-challenges faced by the display industry in general and focuses on solutions that can be achieved in the area of TVs in particular.

Another paper of interest is "A Novel Approach to Make Flexible Active-Matrix Displays," by Jang Lin Chen of ITRI, which discusses how a TFT backplane was successfully developed with a polyimide (PI) substrate and a novel de-bonding technology.

Display Measurement: Critical Measurements for 3-D

This year, Display Measurement features oral sessions in two vital and timely areas: 3-D and Contrast and Motion Artifacts. 3-D is of course a hot technology at Display Week this year, and cross-talk between left- and right-eye imagery that degrades the stereoscopic effect is what Display Measurements' Chair Stephen Atwood describes as "a fundamentally critical concern" for stereoscopic displays. "The principle challenge is finding ways to measure stereoscopic displays in terms of things that matter," he says. Three display-measurement papers that aim to do just that are "Crosstalk Simulation for Polarization-Switching 3-D LCD," by Youngji Ko of Samsung Electronics Co., Ltd., "Crosstalk Suppression by Image Processing in 3-D Displays," by Yu-Cheng Chang of National Chiao Tung University, and "Crosstalk Evaluation of Shutter-Type Stereoscopic 3-D Displays," by Cheng-Cheng Pan of Chi Mei Optoelectronics Corp.

A companion session, notes Atwood, similarly investigates autostereoscopic (3-D with no glasses) display measurements. Of particular interest here is "Characterization of 3-D Image Quality of Autostereoscopic Displays: Proposal of Interocular 3-D Purity," in which Tsutomu Horikoshi of NTT DOCOMO proposes the concept of "interocular 3-D purity" to indicate the image quality of autostereoscopic displays.

Another paper of interest is "Proposal of Evaluation Method for Local-Dimming Back-lights," by Hideki Ichioka of Sharp Corp., which explains a defect named "halo" that is specific to displays with local-dimming backlights, and proposes a method to evaluate the defect.

Display Systems: HUDs, HMDs, and More

3-D was the big news in last year's Display Systems track – so much so that for 2010, 3-D has its own dedicated sessions. This year, with 10 sessions covering not only 3-D, green technology, and solid-state lighting in joint sessions, but HMDs (head-mounted displays) and HUDs (head-up displays), LED backlighting, and novel and emerging display technologies, the Display Systems track has a great deal going on.

In the HMDs and HUDs session, the Invited Papers "Modern Cockpit Displays and Concepts," by Jean-Noel Perbet of THALES Avionics, and "Head-Mounted Display: Optical Design," by Jannick Rolland of the University of Rochester, cover, respectively, a human-centered cockpit system designed to improve overall safety, and a new design for an HMD.

Other papers of note are Distinguished Paper "Control of Subjective Depth on 3-D Displays by a Quantified Monocular Depth Cue," by Shuichi Takahashi of Sony Corp., which considers the architecture and effectiveness of new algorithms that handle the subjective depth of 3-D displays, and "LED Backlighting for LCD TVs," by Winfried Schwedler of Osram Opto Semiconductor, which provides an overview of the issues surrounding the fast-growing market for LED-backlit LCD TVs.

Emissive Displays: Plasma Prevails

"Plasma displays continue to be a growing application area and the papers in this area dominate EMD," says Emissive Displays Chair Gerrit Oversluizen from Philips Research Laboratories. "A lot of research is aimed at continuing the decrease in power consumption that is particularly relevant for large screen sizes. These developments go hand in hand with less material use; i.e., an increasingly green technology." On the technical side, he notes, this impetus involves increasing the xenon content of the gas mixture and implementing protective layer improvements as well as electronics and driving adaptations.

He also observes that "plasma displays are starting to explore 3-D applications. Plasma-display technology, with its relatively fast response time, appears rather suited for this application." Consequently, a paper not to be missed is "Development of High-Performance Panel and High-Speed 3-D Driving Technol-ogy for the World's First Full-HD 3-D Plasma Displays," by Mitsuhiro Ishizuka of Panasonic.

Other papers to watch for are "Very Sensitive Measurement Method of Plasma-Display Exoemission," an Invited Paper by Larry Weber, and "A Consideration of Excitation and De-excitation Process of MgO Protective Layer," by Hiroshi Kajiyama of Hiroshima University, which discusses the dynamics of trapped electrons and holes in the protective layers of ACPDPs, which are important to an understanding of the electron emission mechanism.

Field-Emission Displays

Field-emission-display (FED) color-TV projects, once a focus for many display companies, are no longer much in evidence at Display Week, but this year's submissions show ongoing FED research in a number of promising areas. Among these submissions are the Invited Paper "Full-Color Quantum Dot Display," by Byoung Lyong Choi of Samsung Electronics Co., Ltd., which discusses advanced pattering methods for large-area full-color quantum-dot displays and Distinguished Paper "Switching of Carbon-Nanotube Emitters with Integrated MOSFETs," by Kyu Chang Park of Kyung Hee University, which provides an investigation of the use of metal-oxide-semiconductor field-effect transistors (MOSFETs) for stabilizing and controlling emission currents.

Another paper of interest is "Fabrication and Properties of Planar-Gate-Type Triode with CNT Emitters for Backlight Units," by Yong Zhang of Fuzhou University," which presents a description of how a planar-gate-type triode with CNT emitters was fabricated with photolithography, wet etching, and electrophoresis deposition.

Symposium at a Glance

Flexible Displays: Color Comes Closer

In 2009, due to the ever-increasing number of flex-related submissions, Flexible Displays had its own dedicated sessions for the first time. This year, the submissions relating to electronic paper, flexible-display manufacturing, and flexible backplanes have continued to roll in. Several offerings outline new types of e-readers, and at least five tackle perhaps the hottest of flexible-display issues: color. Papers on color include "Large-Sized Full-Color eReader Displays Based on Electro-wetting," by Johan Feenstra of Liquavista BV, "Flexible Electrofluidic Displays Using Brilliantly Colored Pigments," by Kenneth Dean of Gamma Dynamics, "4.8-in. QVGA Color Reflective AMPDLCD Driven by Printed OFETs," by Joo Young Kim of Samsung Electronics Co., "Research of Various Mode Color PDLC Structures for Flexible Reflective Display," by Jae-eun Jang of Samsung Advanced Institute of Technology, and the Invited Paper "Dyed Polymeric Microparticles for Color Rendering in Electrophoretic Displays" by Mark Goulding of Merck Chemicals, Ltd. Goulding's presentation will describe how, when formulated as colloidal dispersions in low dielectric media, a range of dyed polymeric microparticles with tunable size, charge, and color can be developed that is suitable for use in full-color or monochrome electrophoretic displays.

Other papers of interest include "ZnO TFTs and Circuits on Flexible Polymeric Substrates by Low-Temperature PEALD," by Thomas Jackson of Penn State University, which reports on the use of a novel, weak-oxidant plasma-enhanced atomic-layer-deposition (PEALD) process at 200°C to fabricate stable, high-mobility ZnO TFTs and fast circuits on glass and polyimide substrates. "High-Performance Organic-Inorganic Hybrid Plastic Substrate for Flexible Displays and Electronics," by Jia-Ming Liu of ITRI, reports on an inorganic dominated silica/polyimide (PI) hybrid film that has been successfully developed for the fabrication of flexible AMOLEDs.

Liquid-Crystal Technology: Greener, Better Optical Performance, Lower Cost

Liquid-crystal technology is mature and well-established, according to Chair Birendra Bahadur of Rockwell Collins. It is the standard by which other display technologies must be measured and is, though continuously improving, not in a time of great transition. "The only evolutionary topic in LCT is blue-phase LCDs," says Bahadur. Accordingly, a Distinguished Student Paper that symposium goers should be sure to check out is "Low-Voltage Blue-Phase LCDs with Patterned Electrodes," by Linghui Rao of the University of Central Florida, which outlines an approach that would enable blue-phase LCDs to be driven by a-Si TFTs.

While other changes to LCDs are incremental, they are not inconsequential, particularly at a time when both governments and consumers are demanding greener products. "Displays are becoming greener and more environmentally friendly," says Badahur. "Newer LCDs are cutting the power consumption, weight, and cost substantially." One example of advances in this area is the recommended paper, "Development of Low Haze VA Compensation TAC Film and Proposal of Compensation Film Arrangement for Improving CR in VA Panel," by Eiichiro Aminaka of FUJIFILM, which aims at enabling high-contrast ratio, low-power-consumption LCDs. Last, Badahur continues, viewing angle, color gamut, and video performance are better than ever. "And, LCDs are becoming cheaper and more affordable, even to consumers in very-low-income parts of the world."

Other papers of interest include "The World's First Photoaligned LCD Technology Applied to Gen 10 Factory," by Koichi Miyachi of Sharp, which describes a factory procedure that improves the transmittance, contrast ratio, and response time of LCD TVs. "A Novel Hole-Induced Vertical-Alignment LC Mode with Superior Transmittance," by Yong Kyu Jang of Samsung Electronics, outlines a new liquid-crystal mode, refered to as the Hole-Induced Vertical-Alignment (Hi-VA) mode, which uses a via hole of an organic layer on a TFT substrate to achieve multi-domain alignment.

OLEDs: Moving Beyond Mobile Phones

"This year, we're seeing OLEDs deployed in more non-conventional and unique applications, beyond just mobile devices/TVs," says Eric Forsythe, new OLED subcommittee chair. The technology is starting to mature to a point where we can start building demonstrators and go beyond conceptual drawings into actual applications. There's also a strong green story because of OLEDs' low power consumption. In all, OLEDs open up new design spaces and opportunities, such as the foldable applications and ultimately flexible and rollable ones. From a manufacturing perspective, one of the reasons that folks push hard on OLEDs is the potential for low-cost manufacturing, provided that some technical hurdles are overcome."

One of the papers to look for, according to Forsythe, is Distinguished Paper "LTPS-Based Transparent AMOLED," by Young Woo Song of Samsung. Transparent-display technology might be used for, among other applications, store windows, personal navigation devices with augmented reality, and automobile displays mounted in windshields. Says Forsythe," Samsung has fabricated a nice-looking display for a notebook PC that is reasonably transparent (38%) and will be demonstrating both the technical results and the actual display itself. This should create a lot of buzz." Another strong paper is "The High Performance Scalable Display with Passive OLEDs," by Nobuo Terazaki of Mitsubishi Electric Corp., which discusses the development of large-area OLED displays for billboards and other signage. "This is just another example of how we're looking at OLEDs for non-conventional applications beyond mobile and television."

Another recommended paper is "A New Seamless Foldable OLED Display Composed of Multi Display Panels," by HongShik Shim of the Samsung Advanced Institute of Technology, which describes the creation of a foldout display (for larger viewing area) for mobile devices and similar applications.

Projection Displays: Large and Small

Projection submissions for 2010 cover a gamut of technologies: stereoscopic projection displays, solid-state lighting, mobile projection, and projection components. One of the most significant offerings in this area is the Invited Paper "The Physics and Commercialization of Dual Paraboloid Reflectors for Projection Systems," by Kenneth Li of Wavien, Inc., which discusses how dual paraboloid reflectors (DPRs) work as imaging devices, as well as the advantages of DPRs.

Other papers of interest include Invited Paper "High-Resolution Microdisplays for Pico-Projectors," by Karl Guttag of Syndiant, which outlines how higher-resolution microdisplays have been developed by using liquid crystal on silicon (LCOS) combined with a distributed memory and digital processing. The Invited Paper "Speckle Suppression by Means of Ferroelectric LC Cell," by Igor N. Kompanets of Lebedev Physical Institute of RAS, discusses how unwanted speckle-noise can be eliminated.

Come Get Inspired

Last year, touch, solid-state lighting, 3-D, and green technology came to the front as exciting new areas of display technology. Consquently, SID has added new sessions in these areas. But great discoveries and advances are taking place everywhere in the display industry. The Symposium is an excellent place to learn about new manufacturing processes and materials that could give your business the edge it needs. You might just discover something completely invaluable and unexpected. Come get inspired at Display Week 2010. •