Passive-Matrix Polymer Light-Emitting Displays

Abstract

Organic light-emitting device research focuses on the use of small-molecule and polymer materials to make organic electroluminescent displays, with both passive-and active-matrix technologies. This paper will focus on the characteristics of red, green, and blue electroluminescent polymers suitable for fabricating monochrome and full-color passive-matrix displays. The stability of polymer OLEDs, and the use of ink-jet printing for direct high-resolution patterning of the light-emitting polymers will also be discussed. It will be shown that the performance of light-emitting polymers is at the brink of being acceptable for practical applications.

High-efficiency polymer LEDs : triplets and novel devices

“…Fraction of charge carriers that produce excitons, in particular charge balance ("no recombination" in figure 1). In a standard PLED [1][2][3] , no confinement layers for electrons or holes are present, and balanced electron and hole partial currents are achievable only by tuning of the mobility and injection of either charge carrier. 2.…”

“…One of the building blocks is 9,9'-dialkyl- [3,3']-bicarbazolyl ( figure 11, 1), which is built into the main chain of the polymer such that all sites prone to the oxidative degradation known in carbazoles, are protected. The other building block of the copolymer is either 2,5-diphenyl- [1,3,4]-oxadiazole ( figure 11, 2) or 9,9-bis[4-(3,7-dimethyloctyloxy)phenyl]fluorene ( figure 11, 3), which ensures a reasonable charge carrier balance by adding electron transport character to the copolymer. In this class of carbazole copolymers, the delocalization of triplet excitons can be limited such that the copolymers have a triplet energy of about 2.6 eV.…”

“…Fundamental understanding and rational design of materials and devices has led to major improvements in operational lifetime and efficiency, luminance and driving voltage. In parallel, the necessary technology for large-scale manufacturing has been developed 1 . There are several benefits of polymer LEDs, or organic LEDs (OLEDs) 2 in general.…”

Hole transport in polyfluorene-based sandwich-type devices: Quantitative analysis of the role of energetic disorder

“…The efficiency of organic light-emitting diodes ͑OLEDs͒, which are currently being developed for display 1,2 and lighting 3 applications depends crucially on the electron and hole mobilities. In single-layer OLEDs with ideally injecting contacts, e.g., the ratio between the electron and hole mobilities determines the shape of the recombination profile, 4 and thereby the outcoupling efficiency.…”

Diffuse Interface Modeling of Droplet Impact on a Pre‐Patterned Solid Surface

“…In addition, since printing patterns are digitally generated, it is a flexible process. To utilize these advantages, recently efforts were focused on making ink-jet printing a viable technique for manufacturing a range of different functional materials and devices, for example, thin film transistors, [1,2] DNA microarrays, [3] light-emitting diodes, [4,5] micro-lens, [6] and others. [7,8] Functional materials and devices are used in existing and emerging applications in diverse fields such as microelectronics, optoelectronic, biomedics, ceramics, and so on.…”