THIOPHENE POLYMERS IN LIGHT-EMITTING-DIODES - MAKING MULTICOLOR DEVICES

We can control the bandgap of thiophene polymers over 2 eV by choosing the nature, position and regularity of side chain substitutions. Electroluminescence from these polymers cover the full visible spectrum, from the blue into the near infra-red. Blends of these polymer materials allow us to construct voltage controlled variable colour light sources. A newly developed transfer technique allow us to mount thin oriented films of the polymers in polymer LEDs to obtain polarised light sources giving polarisation anisotropy's of up to 3. Sub-lambda light sources have been constructed from these polymer materials using nanometer polymer electrodes.