ABSTRACT
This chapter begins with a general review of the material requirements for organic light-emitting devices (OLEDs) and organic lasers. It describes how liquid crystallinity offers the benefits of polarized light emission, enhanced light outcoupling and improved carrier transport. The efficiency of any type of OLED depends very strongly on the nature of the materials used. Light-emitting and liquid crystalline small molecules, oligomers, polymers and polymer networks can be used to generate plane polarized light, which is promising for many applications. The mobility of amorphous organic small molecules and conjugated polymers is limited by disorder. A polaronic hopping model also gives a similar result by balancing the temperature-enhancing and temperature-inhibiting terms. Polyfluorene adopts a helical configuration and intra-chain coupling between twisted monomer units rotates the magnetic transition dipole.
