Display Industry Sees Wholesome Benefits in Organic Material

摘要

Organic light-emitting diode (OLED) displays are beginning to gain market recognition. Proponents have positioned OLED as a technology that could replace LCDs in virtually all flat-panel uses. The tremendous potential of OLEDs arises from their ability to emit light (self-emission). In contrast, LCDs can either transmit or reflect light (hence the terms "trans-missive" and "reflective"), but they require an external light source. Emissive displays, OLEDs included, do not need backlights, polarizers, color filters, alignment films, brightness enhancers, or viewing-angle films. Elimination of these items greatly lowers the costs for materials when making such displays. Perhaps no other display technology has captured the attention of the display industry like OLEDs have. At least 30 companies participate in, or plan to enter, the OLED field (Fig. 1). Essentially, OLED displays consist of one piece of glass―which engineers soon will replace with a plastic coating―as well as the anode, the cathode, the organic material, and the backplane. The organic material is readily available from several sources, so its cost has no substantial effect on the total display cost. Emission occurs when an extra electron from the cathode and an extra hole from the anode recombine in this organic material, which engineers dope to emit red, green or blue light.