J. William Doane
Advances in flat-panel display technology, as in many technologies, are largely driven by the discovery of new or improved materials. The electroluminescent (EL) display, for example, would capture a larger share of the market today if there were a more suitable blue or white EL phosphor available to provide a full-color display. Professor S. Kobayashi of Tokyo University of Agriculture and Technology points out that liquid crystal materials possess characteristics that allow them to meet basic criteria for a display: good viewability (legibility, full-color capability, gray scale, view angle); low-cost driving circuits; high information content resolution; low production costs; and light weight. This is perhaps the reason for Japan's multibillion dollar investment in liquid crystal displays (LCDs). There are still many material problems with LCDs. For example, Professor Kobayashi further points out, there remains a need for materials that will give a front-lit passive display. Nearly all of the manufacturing investment in Japan is for backlit displays; and in many ways, use of a backlight defeats the purpose of the passive liquid crystal material.
One of the goals of this study was to determine what Japanese scientists and industrialists consider to be principal limitations in display materials and to identify efforts to overcome these limitations. Because of the massive effort in LCD production and because the JTEC panel was made up primarily of experts in the LCD field, this review is heavily weighted toward LCD materials. These materials will be discussed first.