Integrating photonic microstructures into organic light-emitting diodes (OLEDs) has been a widely used strategy to improve their light out-coupling efficiency. However, there is still a need for optical modelling methods which quantitatively characterise the spatial emission pattern of microstructured OLEDs. In this paper, we demonstrate such rigorous calculation using the reciprocity theorem. The calculation of the emission intensity at each direction in the far field can be simplified into only two simple calculations of an incident plane wave propagating from the far field into a single cell of the periodic structure. The emission from microstructured OLED devices with three different grating periods was calculated as a test of the approach, and the calculated results were in good agreement with experiment. This optical modelling method is a useful calculation tool to investigate and control the spatial emission pattern of microstructured OLEDs.

A series of uniform polymer/amorphous silicon hybrid structures have been fabricated by means of solution-casting for polymer and radio frequency excited plasma enhanced chemical vapour deposition for amorphous silicon (a-Si:H). Poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) functioned as a photoactive donor, while the silicon layer acted as an acceptor. It is found that matching the hole mobility of the polymer to the electron mobility of amorphous silicon is critical to improve the photovoltaic performance from hybrid cells. A three-layer p-i-n structure of ITO/PEDOT:PSS(200 nm)/i-Si(450 nm)/n-Si(200 nm)/Al with a power conversion efficiency of 4.78% under a standard test condition was achieved.

In the present work, the authors have studied conductive surfaces on polyester fabrics by using two types of commercially available conductive polymers; polyaniline and poly (3,4-ethylenedioxythiophene)-poly (styrenesulphonate) (PEDOT: PSS) with 100 nm aluminium thin film evaporated on top of the polymer so the fabric becomes a conductive substrate for inorganic thin film solar cells. Conductive polymer surfaces on woven polyester fabrics were obtained by knife-over-table coating technique. Surface resistivities for polyaniline and PEDOT: PSS coated fabrics were measured and found in the range of 400 × 10 3 and 1 × 10 3 Ω/□, respectively. Thermal stability tests were carried out to evaluate the effect of specific periods of heal treatment at different elevated temperatures on resistance of polymer coated conducting textiles. PEDOT: PSS exhibited better stability than panipol. According to long term tests, PEDOT: PSS coated samples showed improvement in conductivity over 3 days whereas panipol showed the opposite. Transmission Line Model tests were performed to measure aluminium/polymer contact resistances which were found to be 120 × 10 3 Ω for polyaniline and about 46.3 Ω for PEDOT: PSS. Mechanical bending tests for aluminium/ PEDOT: PSS/fabric samples showed that the polymer can maintain the conductivity of samples by bridging micro-cracks in the metal film.

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