13-02-2016, 11:06 AM
INTRODUCTION
Light emitting polymers (LEPs) or polymer-based light-emitting diodes discovered by Friend et al in 1990 have been found better than other displays like liquid crystal displays (LCDs), vacuum fluorescence displays, and electroluminescence displays. Though not commercialized yet, these have proved to be a milestone in the field of Flat Panel Displays (FPDs). Research on LEP is underway in Cambridge Display Technology Ltd, CDT, Cambridge, UK. The Cathode Ray Tube (CRT), invented by German physicist Karl Ferdinand Braun in 1897, remained the ubiquitous display in the last half of the 20th century. But the CRT’s long heritage in an environment where product life cycles are measured in months rather than years doesn’t mean that it is an ideal display solution. It is bulky, power hungry and expensive to manufacture.
The fact is that researchers haven’t come up with a better solution. Liquid Crystal Display (LCD) was pitched as the savior of the display industry. Its creators claimed that a slim profile would quickly make it the display of choice. But today, LCDs are far more pervasive. These offer a little bit benefit over their predecessor, the CRT. The cost of a LCD as well as a CRT monitor one-third of the total price of a computer. Says David Mentley, Vice President and display industry analyst at Stanford Resources, California, USA, “Although LCD is a highly successful technical achievement, the manufacturing archetype must change if flat panel displays are to compete directly across all applications.” In the last decade, several other contenders, such as Plasma and field emission displays were hailed as the solution to the pervasive display. Like LCD, they suited certain niche applications, but failed to meet the broad demands of the computer industry.
What if a new type of display could combine the characteristics of a CRT with the performance of an LCD and the added design benefits of formability and low power? Cambridge Display Technology Ltd (CDT) [1] is developing a display medium with exactly these characteristics. The technology uses a light emitting polymer (LEP)[2] that costs much less to manufacture and run than CRTs[3] because the active material is plastic.