With a Little Help from Our Friends
by Stephen P. Atwood
Here at Information Display we have been covering the slow but steady progress of OLED technology for more than 8 years. In 2005, then editor Ken Werner stated that “Organic light-emitting-diode (OLED) display technology is the only serious current challenger to the LCD’s hegemony in small- and medium-sized displays….” It took a few more years for OLED displays to really penetrate the mobile-display market, first as secondary phone displays and then as primary displays. By 2011, we were looking at 180 million units shipped and active-matrix OLED display revenues climbing above the $10 billion annual sales mark, as reported in the October 2011 Display Marketplace article, “OLEDs in Transition.”
That’s still small potatoes compared with the total market for LCD mobile devices, but it is significant from the standpoint of infrastructure investment, process development, materials and chemistry supply chain, etc. It’s also significant when you consider the substantial dominance of LCD technology and its relentless march toward higher resolutions and ever-improving optical performance. It is hard to close the performance gap when the competing technology continues to improve in so many dimensions.
It was also in 2005 that Samsung stunned the display world when it first demonstrated a 40-in. prototype OLED TV. This breathtaking prototype used a white emitting layer with color filters and utilized amorphous-silicon (a-Si) TFTs in the active backplane – at a time when many others were working on low-temperature polysilicon (LTPS). We learned later that a-Si was not going to be the best approach for OLED TFTs, but the game was on in terms of defining the future for OLED as a competing technology for large-format TVs as well. And why not?
Samsung demonstrated what we all anticipated that OLEDs had several intrinsic performance advantages over LCDs owing to their nature as an emissive technology, including power consumption based on content, true black levels and very wide dynamic range, tunable color spectrums, and very fast response times. OLEDs also promised advantages from a process perspective that would make any size panel easier to produce than an LC-based one. More TV prototypes followed, and Sony even commercialized a small-format 11-in. OLED TV. But the challenges of actually producing large volumes of any size OLED TV were daunting, and a lot of practical challenges remained even into 2009, as reported in ID by Barry Young in his article “OLEDs: Promises, Myths, and TVs” in the September 2009 issue. At that point, a-Si backplanes were out and oxide-TFT and LTPS backplanes were still in development. It took another 3 years before the first truly production-ready OLED HDTV demonstrations appeared at CES and Display Week. Those 55-in. wonders made true believers out of us all, even though their availability was still somewhat of a mystery.
Well, here we are in 2013 and you can finally go to your favorite big-box retailer and buy a 55-in. OLED TV for slightly less than $10,000. It’s a miracle! Well, actually it is more of a milepost in our industry now and the culmination of an unfathomable amount of work by countless industry experts and visionaries, some who have graciously been helping us report on this technology for so many years. And so, as we approach the end-of-the-year shopping season, we thought it fitting to put the Samsung and LG 55-in. curved OLED TVs on our cover.
These TVs are also the subject of our first Frontline Technology article this month. Being good engineers and scientists, we do not generally spend too much time gushing over new creations. We like to get our brains busy scrutinizing and analyzing them instead, and no one is better at this than well-respected industry metrologist Dr. Edward Kelley. Ed got his hands on one of each of these 55-in. OLED TVs and hustled them over to his optical measurement lab, where he got to work not only testing their performance but also road testing his new ideas for OLED display metrology that will soon appear in the next revision of the ICDM Display Measurement Standard (DMS).
In the first in a series on this research titled, “Considering Color Performance in Curved OLED TVs,” Ed reports on the color and video performance of the two TVs as well as the methods for getting accurate and reproducible measurements for comparison. There are clear differences in performance between today’s OLED and LCD TVs, and there are some differences in performance between the two OLED TVs. It’s too early to declare a winning technology, but for an almost perfect HDTV viewing experience these curved OLEDs are certainly ready to deliver.
However, one attribute that LCD technology can still claim dominance in is the ability to scale to extremely large sizes, such as 110 in. The most recent achievement in this area is the world’s first LCD panel to offer 4K × 2K resolution and 3-D capability – and China Star Optoelectronics Technology did it at 110 in., with a luminance of 1000 cd/m2 and an amazing 50000:1 dynamic contrast ratio. In their Frontline Technology feature titled, “Developing a 110-in. 4K × 2K TV,” authors Li-Yi Chen et. al. explain why 4K × 2K resolution is important for panels in this size range as well as how much more immersive the really large screen experience can be.
There were actually several very complex technologies combined in this effort, including a two-dimensional dynamic LED backlight, a novel pixel addressing and driving scheme, and a custom video system architecture that includes custom calibration algorithms to optimize the panel performance in various ways. We were especially pleased with the very detailed explanation of how the developers overcame the challenges of tiling many side-by-side photolithography exposures to form the internal structures of the panel and how they overcame the charge time limitations in a panel this size. For those of us who do not work on the manufacturing side of LCD technology, this represents a rare and very vivid glimpse into the kinds of challenges that must be overcome by innovative manufacturers like China Star. I really learned a lot from this article and I think you will also. By the way, we thought it fitting to add this display to our cover as well.
Continuing with our theme of large-area displays, we also turn our attention to digital signage. To get a glimpse of the state of this industry, we invited veteran contributor Terry Schmidt to serve as our Guest Editor this month. Terry explains in his guest column, “Digital Signage that Captivates,” how far the industry has come in the last few years owing to the reduction in prices for large-area displays suitable for signage applications as well as a rapid expansion of the tools available to create and manage sign content. Without a content infrastructure that is affordable and easy to implement, the ROI for a digital sign system just will not add up. But those ingredients now exist, and the recent proliferation of so many novel developments is a testimony to this.
One new development that could become a player in this market is the Emissive Projection Display (EPD) with a transparent fluorescent screen described by authors Ted X. Sun and Botao Cheng in our next Frontline Technology feature titled, “Novel Emissive Projection Display Digitizes Glass Windows.” Just imagine, if you can, a digital image that appears to be floating in mid-air that is visible from any 2-D viewing angle. Traditional projection systems require opaque or translucent screens to render their images. Transparent LCDs can render seemingly floating images but require a strong local source of ambient light for viewers to see them. The EPD system, however, produces the viewable image by fluorescent emission, very similar to how phosphor screens on CRTs operate. The result is a self-illuminated image that can appear on any transparent glass surface driven by front or rear UV light projection. This technology was first presented at Display Week 2013 and is now described for us in detail in this issue.
Of course, digital signage is driven by commerce and culture. Different regions have different commercial and cultural needs. In Europe, there are somewhat unique cultural barriers to widespread deployment caused by the diversity inherent in the many different countries that make up the region. As we learn from author and analyst Bob Raikes in this month’s Display Marketplace feature titled, “Public Displays in Europe (and Elsewhere),” there is no one formula that can work across the entire European market, and even trying to think of the continent as one large market for digital signage is probably not worthwhile. Bob did a great job of breaking it all down for us in many different dimensions and his analysis shows what Terry Schmidt also said, that the recipe for success must include low-cost high-value content creation and distribution that is regionally targeted.
The overall display marketplace in Europe is very complex, owing in part to the vast diversity of independent countries involved – diversity in terms of culture, economic standing, consumer preferences, historical factors, etc. Europe has been slower to recover from the economic recession and the European Union countries tend to lead the way in areas like environmental regulations and ergonomic standards, making it harder to do business there than in other parts of the world. Nonetheless, there is a plethora of innovation, development, and consumption opportunities to be seen when you dive into the details, as our own Jenny Donelan has done for the next installment in our Regional Business Review, “The Display Business Environment in Europe: Together but Different.” Jenny explains how in several ways the consolidation of regulation and standards activities within the EU makes it easier to navigate and negotiate business than it used to be. Also, European companies continue to make some of the most important contributions to display technology such as liquid crystals from Merck, measurement technology from Eldim, and OLED materials from Novaled, and, of course, the innovative and ever popular display-based consumer products from Nokia.
Our last but hardly least feature this month is the next installment in our Venture Capital series by Helge Seetzen. In this month’s article titled, “The Ins and Outs of Venture Capital,” Helge tackles the thorny details of venture funding: valuations, preferred stock, dilution, liquidation, and other things you need to understand before diving in to your new venture. If you are lucky enough to cash out someday with heady gains after all your efforts, I hope you will send Helge a thank you note for his hard work and dedication in compiling this groundbreaking series for Information Display that will continue next month as well.
And so, here we are at the end of another great year for Information Display. I sincerely hope all of you have a great holiday season and have enjoyed the efforts of our truly dedicated staff, including our Managing Editor Jenny Donelan, our Editor-in-Chief Jay Morreale, our colleagues at Wiley publishing, Simone Taylor and Joseph Tomaszewski, and the continuing support of the SID Executive Committee, Publications Committee, and all our great Guest Editors throughout the year. Without the relentless efforts of these people, ID would literally cease to exist.
There is one more person I want to mention before I close – our Editorial Advisor Allan Kmetz. Allan has been a mentor and trusted advisor to ID for many years. Allan reviews and edits the final copy of practically every feature article that goes into ID, bringing to the task both a strong technical perspective as well as a great sense of clear language and style. Many times he unlocks details we do not fully understand or reminds us of things that may be confusing to readers not so skilled in the art. It is hard to overstate how much he has contributed to the accuracy and integrity of this endeavor.
Beyond his role with ID, Allan Kmetz is a Fellow and Senior Member of SID as well as a Past-President. He is an active member and past-officer of the SID Mid-Atlantic Chapter. He has served as both lecturer and organizer of the SID Seminars and as a program committee member, program chair, and general chair of the SID Symposium and the IDRC. We are all grateful and look forward to Allan’s continued support of ID in the coming year.
From all of us at ID, we wish you a safe, healthy, and prosperous holiday season. •