Geometry-dependent absorption, and emission of Para-hexaphenyl

The optical properties of highly oriented films of para-hexaphenyl, a conjugated material which is suitable for blue light emission applications, were investigated. Wave-guiding calculations, with anisotropic optical coefficients were combined with angle-dependent photoluminescence measurements, and single-layer device electroluminescence. The microstructure of the vacuum-deposited films is controlled by the deposition method, allowing tuning of the optical properties. We propose optimal configurations for light output with LED's and optically pumped device applications.