Eine Halbleiterdiode mit externer Kavität wird um eine Messzelle speziell für Gase erweitert. Diese erlaubt Absorptionsmessungen einer exakt definierten Menge von Gas unter kontrollierten Temperatur- und Druckbedingungen. Es werden konzentrationsabhängige Absorptionsmessungen mit Propofol durchgeführt. Als Ergebnis werden effektive Pfadlänge, Bestimmungs- und Nachweisgrenze berechnet und der Beweis erbracht, dass beide im System anschwingenden Moden in Konkurrenz zueinander stehen. Weiterhin wurde eine ausgeprägte ...

Tunable Optical Sensor Arrays (TOSA) based on Fabry-Pérot (FP) filters, for high quality spectroscopic applications in the visible and near infrared spectral range are investigated within this work. The optical performance of the FP filters is improved by using ion beam sputtered niobium pentoxide (Nb2O5) and silicon dioxide (SiO2) Distributed Bragg Reflectors (DBRs) as mirrors. Due to their high refractive index contrast, only a few alternating pairs of Nb2O5 and SiO2 films can achieve DBRs with high reflectivity ...

Micromirror arrays are a very strong candidate for future energy saving applications. Within this work, the fabrication process for these micromirror arrays has been optimized and some steps for the large area fabrication of micromirror modules were performed. At first the surface roughness of the insulation layer of silicon dioxide (SiO2) was investigated. This SiO2 thin layer was deposited on three different type of substrates i.e. silicon, glass and Polyethylene Naphthalate (PEN) substrates. The deposition ...

In this thesis, a dual mode tunable gas sensor based on intracavity laser absorption spectroscopy (ICLAS) principle is investigated, both, numerically and experimentally. In order to minimize the cost and size of the gas sensor, relative intensity noise (RIN) is implemented as a detection parameter. Investigation is performed to determine the effect of injection current, operating temperature, mode spacing, and cavity length on RIN. It has been found that it is best to operate the gas sensor at smaller mode spacing ...