|Bolognesi, A.; Botta, C.; Facchinetti, D.; Mercogliano, C.; Jandke, M.; Strohriegl, P.; Kreger, K.; Relini, A.; Rolandi, R.: Polarized electroluminescence from double-layer LEDs with active film formed by two perpendicularly oriented polymers in ACS: CHROMOGENIC PHENOMENA IN POLYMERS, ACS Symposium Series, 888, 211-219 (2005)|
The aim of this work is to study the feasibility of a double layer device, where the two active materials are formed, respectively, by two oriented polymers, whose orientation direction is orthogonal, and which can emit simultaneously in different regions of the visible spectrum. We demonstrate that the anisotropy of the polymers is not lost when they are perpendicularly oriented, obtaining polarized light in a large spectral region, extending from the green to the red. The emitted light, observed through a polarizer, can be varied from green to red by simply rotating the polarization axis, obtaining polarized light of variable colour. This peculiar device design is particularly appealing as it can increase the versatility of organic LEDs providing polarized light with easily variable colour emission.