33 research outputs found
Synthesis, photophysical and electroluminescent properties of 1,3-diphenyl-1H-benzo[g]pyrazolo[3,4–b]quinoxaline
Abstract Experimental investigations of electroluminescence spectra for new azaacene derivative have been performed. Azaacene was used as dopant in {PVK} matrices in electroluminescence devices with ITO/PEDOT:PSS/active layer/Ca/Al light-emitting diode configuration. The yellow emission was obtained with the electroluminance of 1530 cd/m2 at 15.0V
Silica-Titania Films Fabricated by Sol-Gel Method for Applications in Planar Photonics
The work presents silica films produced with sol-gel method of extremely different refractive indices as well as two-component waveguide films of very low attenuation
Planar Optical Waveguide Sensor Structures with Grating Couplers
The paper presents optical planar waveguide sensor structures with grating couplers of groove density χ = 2400 g/mm. The waveguide films were obtained using sol-gel method, in which the grating couplers were fabricated by the embossing method. The results of theoretical analysis as well as the results of experimental research have been presented
Sensitive Films for Optical Detection of Ammonia and Nitrogen Dioxide
The sol-gel technology allows preparation of the thin silica films ranging in porosity from dense to highly porous. These films can function as matrix binding molecules of pH-sensitive indicators and can be utilized as sensitive coatings for intensity based planar evanescent wave chemical sensors. This paper is devoted to manufacturing technology and characterization of highly porous silica films deposited on soda-lime glass substrates, impregnated with bromocresole purple and cresole red. Two different methods of impregnation were used: dip coating, which entails sensitization of both silica films deposited on each side of a substrate and selective deposition of a dye solution on single side of the substrate. Manufactured sensitive films were tested toward influence of gaseous ammonia and nitrogen dioxide on their spectral characteristics of the absorption coefficient and the imaginary part of the refractive index. It was shown that bromocresole purple allows detection of both gases: and
Planar Evanescent Wave Ammonia Sensor - Influence of Refractive Index Profile on Sensor Properties
The paper presents the results of the investigations involving the influence of the change of launching conditions on the characteristics of the planar amplitude evanescent wave ammonia sensors. Investigated sensors are based on the channel gradient waveguides, which are produced with the application of the ion exchange in glasses. In our investigations we have tested two sensor structures of different refractive index profiles. The absorption sensitive films were produced using sol-gel technology
Rib channel waveguides for sensor applications
Zmiany efektywnych współczynników załamania w czujnikach światłowodowych pracujących w oparciu o spektroskopię pola zanikającego mierzone są z zastosowaniem sprzęgaczy siatkowych lub interferometrów. Podstawowym elementem interferometrów planarnych są światłowody paskowe. Przedstawiana praca dotyczy żebrowych światłowodów paskowych. Otrzymywane metodą zol-żel warstwy falowodowe SiO2:TiO2 są selektywnie maskowane z zastosowaniem tradycyjnej fotolitografii a następnie trawione chemicznie. W ten sposób zostały wytwarzane jednomodowe żebrowe światłowody paskowe i sprzęgacze kierunkowe. W pracy przedstawione są wyniki analizy teoretycznej światłowodów żebrowych i wyniki badań eksperymentalnych wytworzonych struktur.Basic elements of planar interferometers are the channel waveguides. Presented work refers to the channel rib waveguides. In our previous work [7] we offered the production method of rib channel waveguides with the application of traditional photolithography and wet chemical etching of sol-gel derived silica-titania waveguide films. In this work we present new results of our research on rib waveguides and directional couplers. The theoretical analysis of rib waveguides was presented as well as the results of experimental investigations on the fabricated structures. The investigations on channel waveguides of the rib height of 5 nm was carried out for wavelengths: λ=677 nm. The waveguide films used in rib waveguides manufacturing technology are characterized by high refractive index (˜1.8) and ultra-low attenuation of 0.15 dB/cm. Rib waveguides of width w<4 Μm are monomode. For the rib waveguides we obtained the attenuation of (1.5š0.1) dB/cm. Rib waveguides of such an attenuation can be applied in the technology of integrated optics systems in sensor applications, and in particular for the construction of interferometers of Mach-Zehnder, Young or Michelson. The improvement of technology, and in particular the improvement in the quality of photolithographic masks should contribute to further decrease of attenuation of the produced rib waveguides