OLED Luminaires: Device Arrays with 99.6% Geometric Fill Factor Structured by Femtosecond Laser Ablation.

The plethora of design opportunities renders organic light emitting diodes (OLEDs) ideal luminaires for general lighting applications. Progressing from lab-scale device concepts to large-area applications calls for smart device designs that are scalable and, at the same time, unsusceptible to resistive losses within the electrodes. By employing direct pulsed femtosecond laser structuring, we fabricate OLED luminaires comprising monolithically interconnected OLED arrays. We determine the laser ablation thresholds and the optimized process parameters for all functional layers. The clean laser cuts with precise ablation depths show no detectable damage to adjacent layers or any ridges, hence avoiding unwanted short-cuts or device isolation. All processes are scalable. The 3-fold structuring of the OLED luminaire is confined within 45 µm and hence below the resolution limit of the human eye, yielding a geometric fill factor beyond 99% and therefore a very homogeneous device perception.

The practial use of the consensus statement on practical skills in medical school--a validation study.

OBJECTIVE: The importance of the acquisition of practical medical skills during medical school is increasing. With the consensus statement "Practical Skills," developed by the GMA as part of the National Competency-Based Learning Objective Catalogue for Medicine (NKLM), a reference frame was created for the procurement of such skills. This frame consists of 290 learning objectives divided by "organ system," type (core or elective learning objective), current stage of medical education and level of instruction. By comparing a large and well evaluated range of student tutorials with the consensus statement, one can analyze the practical benefit of the statement, as well as evaluate the tutorial program for completeness. METHODS: In the first stage, four evaluators in two groups independently classified all consensus statement's learning objectives by each of the 48 tutorials currently offered. The inter-rater reliability among the evaluators of each group was calculated both collectively, and according to each organ system. In the second stage, disagreements in the classification were resolved through discussion and consensus decision-making. The coverage of the learning objectives by the tutorials, in the required level of instruction, was then analyzed separately by learning objective type and organ system. Reasons for any initial dissent were recorded and grouped thematically. RESULTS: The correlation between the classifications of the two evaluators was moderately significant. The strength of this correlation, and thus the precision of individual learning goals wording, varied according to organ system. After a consensus was reached, the results show that the offered tutorials covered 66% of all learning objectives, as well as 74% of the core objectives. The degree of coverage differed according to organ system and stage of medical education. CONCLUSION: The consensus statement is suitable to systematically analyze and develop teaching units. The comparison with established curricula also offers possibilities for further development of the consensus statement, and therefore also of the NKLM.