In the not so distant past, televisions and computer displays contained large and heavy cathode ray tubes (CRTs) to produce their images. Today, however, we use light and thin liquid crystal displays (LCDs), which make televisions and computers a much more attractive and convenient part of our daily lives.
At the same time, LCDs have greatly evolved as well. The tiny, monochrome LCDs of the past have grown into the huge, colorful LCD panels of the present, allowing us to view all kinds of content with ease. But did you know that behind this innovation lies a film developed and produced by Fujifilm? A thin sheet of WV (wide-view) Film enhances our lives in offices and living rooms around the world.
While LCDs have played a role in pocket calculators and watches since the 1970s, it was only in the latter half of the 1990s that they came to be used in computer displays. To create these advanced color displays, a variety of technical challenges had to be overcome to enhance LCD image quality and response speed. Moreover, production costs had to come down to make them reasonably affordable.
At the time, the type of LCD that did the best job of covering the technological and economic requirements was the twisted nematic (TN) LCD.* Yet a TN LCD had one big weakness: when looked at from an angle instead of head-on, the colors and levels of brightness in the image would change. This problem would have made TN LCDs unsuitable for use in large displays, but technological innovation from Fujifilm came to the rescue: WV Film.
In an LCD, the liquid crystal molecules in each pixel play the role of transmitting and blocking light that comes from behind them toward the viewer. When TN LCDs are viewed from the side, above, or below, the characteristics of the liquid crystal molecules cause light that should be blocked to leak out, altering the colors and levels of brightness in the image. WV Film optically compensates the liquid crystal molecules oriented in many directions within the liquid crystal layer of the pixels at black state to prevent the leakage of light. When an LCD with WV Film is viewed from any angle, black appears truly as black.
Thanks to its outstanding performance without changing current LCD production process, WV Film is used in almost every TN LCD panel produced worldwide. In fact, there is a good chance that you are currently viewing this website on a computer LCD that incorporates Fujifilm’s WV Film.
*At the time, the only commercially feasible thin-film transistor (TFT) LCD using an active-matrix structure was the TN LCD. Since an active-matrix structure makes possible control of each pixel via a dedicated transistor that can turn voltage on or off, it offers image quality and responsiveness superior to a passive-matrix structure. In addition, since each pixel can be turned on or off, an active-matrix structure works well in displaying a digital signal.
In the 1990s, LCD panel manufacturers were looking for a solution to the limited angle of view of TN LCDs. Their research consisted mainly of attempting to alter the liquid crystal cells themselves, but any changes they made ended up reducing the transmittance of the cells, creating a weakness equal to the one they were trying to eliminate.
It so happened that Fujifilm had a problem of its own to solve. At the time, super-twisted nematic (STN) LCDs were the main type of LCD on the market. Fujifilm was supplying materials to manufacturers for use in STN LCDs, but the market had grown increasingly competitive, and Fujifilm’s sales in this segment were drying up. Fujifilm’s R&D team for this market was faced with a tough choice: disband or develop a revolutionary new product. As one might expect of a Fujifilm R&D team, they took on the challenge. These five young researchers in their twenties and early thirties were not yet accustomed to defeat and were in no mood to taste it for the first time.
The beautiful image quality of the up-and-coming TN LCD, which was far superior to that of the STN LCD, was all it took to capture the team’s attention and reinforce their spirit of challenge. In the summer of 1993, the team began research into methods of optically compensating the viewing angle of TN LCDs. They only had one rule: think clearly and simply. As a result, they had the insight of developing a film that optically compensated the liquid crystal molecules oriented in many different directions within the liquid crystal layer of the pixels. Clear and simple thinking had led them to an extremely rational potential solution, but they still had no idea of what kind of material could produce the desired effect.
In the winter of 1993, one member of the team discovered a particularly interesting research paper, which described discotic, or disc-shaped, compounds. This was exactly the shape for which the researchers had been searching, since it was the most efficient shape with which to compensate the rugby ball-shaped LCD molecules. The team immediately began experimenting with discotic compounds arrayed diagonally on film. Discotic compounds had never before been used in a commercial product, but the team experimented with a variety of approaches, eventually discovering an effective way to align the molecules. The film had another feature that made it even more unorthodox: the molecules exhibited a hybrid orientation whereby they continuously changed their angle with respect to the film substrate and its interface with the air. Simply putting a sheet of this film on both sides of the LCD panel allowed viewers to enjoy its images from many different angles. The longstanding TN LCD problem of limited angle of view was solved in an instant, and a revolutionary new film was born.
Fujifilm soon began supplying WV Film, as it called the new product, to the LCD panel manufacturers with which it already had partnerships. In 1995, a small LCD TV featuring WV Film was introduced to market. When LCD panel manufacturers around the world saw how the simple application of film could raise performance to such an exceptional level, they quickly adopted the new innovation. In time, TN LCDs panels featuring WV Film would contribute to the further popularization of personal computers and digital television broadcasting. Moreover, they helped hasten the near extinction of the CRT, a technology that was dominant from the middle of the 20th century to the beginning of the 21st.
Technology never stops evolving, and since the advent of WV Film, new types of LCD have appeared, including vertical alignment (VA) and in-plane switching (IPS) LCDs. Since the year 2000, these innovations have further enhanced the performance of digital displays, supported the introduction of smartphones and tablets, and helped enrich the lives of people around the world. TN LCDs and WV Film were foundational technologies that have helped make such innovations a reality, and Fujifilm is proud to have played a key role in change they generated, which has been so clearly beneficial to society.