Share Email Print

Proceedings Paper

Optoelectronic and photonic properties of liquid crystals: electroluminescence and photorefractivity
Author(s): Stephan A. Benning; Marcus W. Lauhof; Lutz Paelke; Andreas Redler; Felix Scheliga; Emma Thorn-Csanyi; Volkmar Vill; Heinz-S. Kitzerow
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

Beyond conventional electrooptic applications, liquid crystals become increasingly important in the topical field of organic electronics. Here, some fundamental findings are reviewed and two examples for the combination of liquid crystals and organic semiconductors are described in more detail. The first part of the paper describes the electroluminescent properties of very thin layers of aligned p-(phenylene vinylene) oligomers, which are embedded in a stack of thin organic semiconductor layers and sandwiched between two electrodes. Both the wavelength of the emitted luminescence (varying from green to red) and the dichroic ratio increase with increasing length of the aromatic backbone of the molecules. High brightness and low threshold voltages could be achieved. The photorefractive system described in the second part of the paper consists of small droplets of a low molar mass liquid crystal, which are dispersed in a photoconducting polymer. Two-beam coupling experiments indicate a high performance at reasonable external voltages. From dynamic diffraction measurements, the amplitude of the internal space charge field can be estimated.

Paper Details

Date Published: 8 February 2007
PDF: 9 pages
Proc. SPIE 6487, Emerging Liquid Crystal Technologies II, 648702 (8 February 2007); doi: 10.1117/12.716598
Show Author Affiliations
Stephan A. Benning, Univ. of Paderborn (Germany)
Marcus W. Lauhof, Univ. of Paderborn (Germany)
Lutz Paelke, Univ. of Paderborn (Germany)
Andreas Redler, Univ. of Paderborn (Germany)
Felix Scheliga, Univ. of Hamburg (Germany)
Emma Thorn-Csanyi, Univ. of Hamburg (Germany)
Volkmar Vill, Univ. of Hamburg (Germany)
Heinz-S. Kitzerow, Univ. of Paderborn (Germany)

Published in SPIE Proceedings Vol. 6487:
Emerging Liquid Crystal Technologies II
Liang-Chy Chien, Editor(s)

© SPIE. Terms of Use
Back to Top