Search results for " DBR"
showing 3 items of 3 documents
Microreflectivity studies of wavelength control in oxidised AlGaAs microcavities
2003
Wet oxidation of GaAs/AlGaAs structures is an important technique in the processing of advanced devices such as vertical cavity surface emitting lasers (VCSELs). In one VCSEL application, the low-index and electrically-insulating AlxOy layers have been used to obtain high-reflectivity and broad bandwidth distributed Bragg reflector mirrors (DBRs). A further recent development has shown that combined lateral–vertical oxidation of intracavity AlGaAs layers can be used to tune the resonant wavelength of a semiconductor microcavity. The slow oxidation rate limits the lateral scale of practical wet oxidation to mesas structures of 50–100 μm in width. Therefore post-processing assessment of spect…
Generazione di modelli 3d e ricostruzione semantica su piattaforma GIS Tecniche e Metodologie
2009
Nell'ambito dei rilievi dei beni culturali è opportuno ed utile trovare sistemi alternativi ed innovativi per il rilievo, la catalogazione e la fruizione virtuale, la riproduzione materica dei modelli generati. La fase di rilievo, nel caso in esame, è stata condotta tramite l'integrazione di rilievo topografico e laser scanner finalizzato alla modellazione tridimensionale di uno dei Telamoni (dimensioni approssimative 6 mt di altezza, posto a circa 10 mt dal suolo) posti sulla Porta Nuova di Palermo ed alla successiva prototipazione. Date le difficoltà tecniche legate ad un rilievo con scanner a triangolazione ottica, per dimensioni e condizione di illuminazione, sono state realizzate scans…
Doing what we teach : promoting digital literacies for professional development through personal learning environments and participation
2015
Despite the proliferation of social media, few learners make effective use of digital technology to support their learning or graduate with the skills necessary for developing and communicating their expertise in the knowledge-driven networked society of the digital age. This article makes use of the concept of Personal Learning Environments (PLE) to approach the question of how digital literacies for learning can be taught and learned in the context of higher education. It presents a model of a PLE course, the overall goal of which was to equip the learners with the skills and competences needed to create their own digital environments that would enable them to tap the online networks and …