{'fraction_non_alphanumeric': 0.018102824040550327, 'fraction_numerical': 0.0, 'mean_word_length': 5.398148148148148, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Refined Setup for Angle-Resolved Photoluminescence Spectroscopy of Thin Films

Angle-resolved photoluminescence spectroscopy is a powerful tool for investigation of the properties of light-emitting thin-film structures. For instance, it can reveal information about the orientation of the transition dipole moment in organic emission layers, which is one of the most important parameters defining the efficiency of organic light-emitting diodes. In this work, a refinement of one of the main experimental configurations utilized for such orientation measurements is presented. The technique is based on a step-by-step rotation of the optically excited layer with respect to the detector. By attaching the sample to a large glass half cylinder, the light initially trapped in the substrate can be extracted. It is shown that by inserting two additional optical lenses between the half cylinder and the detector, the signal-to-noise ratio can be improved by about one order of magnitude. A ray-optics model is derived that describes the light propagation in the macroscopic setup and enables us to characterize the impact of deviations from theoretical ideal measurement configurations. The numerical predictions are experimentally validated analyzing quantum-dot emission layers as an isotropic reference and established organic emitter molecules with well-known orientation values.