As Easy as L-C-D


One of the great benefits we have seen this year since instituting our Guest Editor program is that we get to present a variety of professional styles and frameworks based on the affiliations of the guest editors and their professional leanings. Sometimes the focus is on the commercial product side of the business, often with an applications flavor. Other times the mix is more "how-to-do" with tutorial-style articles and proposed solutions to current industry problems – concepts that are not yet ready for the mass market.

This month, the flavor is decidedly more academic with the focus on the fundamental science of LC technology. Our guest editor, Professor Hoi-Sing Kwok, has arranged for an eclectic but powerful set of articles addressing various research-and-development initiatives in the LC arena. While these articles may be a bit more academically focused than you are accustomed to, they offer great revelations of cutting-edge work that no doubt will lead to interesting results in the next few years. Professor Kwok is the Chair of the Electronic and Computer Engineering Department at the Hong Kong University of Science and Technology and is very active in the display field. He received his M.S. and Ph.D. degrees from Harvard University in Applied Physics in 1974 and 1978, respectively. From 1978 to 1980, he worked at the Lawrence Berkeley Laboratory with Professor Y. T. Lee (Nobel Laureate, 1986). He has been with the Hong Kong University of Science and Technology since 1992.

His choice of articles includes a look at the latest work using pulsed lasers to produce effective polycrystalline-Si films for low-temperature polysilicon (LTPS) TFTs in AMLCD applications. Contributed by James Im et al., this article provides an excellent synopsis of the details and challenges being addressed to drive LTPS technology to "second generation" status. Dr. Im believes this will lead to much higher pixel densities and lower manufacturing costs than the present amorphous-Si TFTs used today.

The next article, contributed by Philip Bos from the Liquid Crystal Institute at Kent State University, provides the keys to understanding the mechanisms of switching speed in nematic LCDs. This is a critical topic to appreciating the efforts related to solving motion-blur effects in LCD TVs, and one that I understood only at a very cursory level prior to reviewing Phil's submission. Even after reading this article and appreciating the problem a lot more, you should still be concerned that as long as LCDs continue to operate as essentially sample-and-hold devices, there will always be a visually perceived motion-blur effect. However, as the switching speeds can be made smaller and smaller, advances in backlighting technology can be employed to bring about a variety of "flash mode" mechanisms that render more "CRT-like" response and will be part of the ultimate solution to this problem.

Our third article also deals with response time and other physical properties of LCs by doping them with nanoparticles of various compositions. Far from being purely theoretical, authors Shunsuke Kobayashi and Naoki Toshima describe actual results and promising behaviors they consider surprising and worthy of further study. I was surprised at how many different types of materials can be used as well as the variety of potentially valuable effects these materials can have on the performance of liquid-crystal displays.

Our final article is not liquid-crystal related but rather addresses an exciting advancement in the field of LED technology – using LEDs as light sources for projection displays. Earlier this year, Luminous Devices was awarded the 2007 Display Component of the Year Silver Award from SID and Information Display for PhlatLight LEDs. Since that time, we have been working with them to get a full article discussing the essential elements of their technology and its application to high-intensity projection-display lighting. Those of us in the northeastern United States have been able to see several demonstrations of their technology at local SID chapter meetings, but until now, the details of how their PhlatLight devices work was a closely guarded secret. I am very pleased to have this submission by Christian Hoepfner, the Vice President of Products for Luminus Devices.

One additional feature of the magazine I want to mention this month is the first of a four-part series on patent technology contributed by Clark Jablon, Esq, a practicing patent attorney specializing in advanced technology and business model intellectual property. I had the privilege of working with Clark recently and immediately realized I wanted him to share his knowledge with the readers of ID. Clark has a refreshingly practical, common-sense approach to IP strategies and building a patent portfolio. His insights are especially timely now in light of the Supreme Court decision in April changing the standards by which the validity of patents may be judged. Therefore, we asked Clark to begin by explaining the court decision and what it actually means to those of us in the display business. In subsequent installments, Clark will continue the series by discussing how the new standards affect your existing portfolio and what you need to do to make it more robust. He will also describe how to evaluate patents from an infringement point of view, and how to create an effective patent program if you do not have one already.

An important part of this series can be you the reader. We would be very pleased to receive questions and inputs on Clark's columns and quite possibly we could address those questions in later installments. So, I hope you will take the time to read these each month and share your thoughts with us by way of e-mail at .