• A miniaturized ball-lensed fiber optic NIR transmission spectroscopy-based glucose sensor 

      Fuglerud, Silje Skeide; Milenko, Karolina Barbara; Larsen Jernelv, Ine; Ellingsen, Reinold; Aksnes, Astrid; Hjelme, Dag Roar (Chapter, 2018)
      A novel ball-lensed fiber transmission sensor is presented aimed at in vivo continuous glucose monitoring of diabetics. Preliminary results yield 20 mM RMSE, limited by mechanical instability. The design enables flexibility ...
    • A rangefinder for measuring vibrations of structures - Optical-FMCW interferometry 

      Grodås, Lars Christian Eriksson (Master thesis, 2014)
      The optical Frequency Modulated Continuous Wave (FMCW) technique along with utilizing the Doppler shift was investigated for the application of monitoring distance to and oscillation of a bridge. The equipment was borrowed ...
    • A Review of Optical Methods for Continuous Glucose Monitoring 

      Jernelv, Ine Larsen; Milenko, Karolina Barbara; Fuglerud, Silje Skeide; Hjelme, Dag Roar; Ellingsen, Reinold; Aksnes, Astrid (Journal article; Peer reviewed, 2018)
      Frequent glucose monitoring is a fundamental part of diabetes management, and good glucose control is important for long-term health outcomes. New types of electrochemical sensors that allow for continuous glucose monitoring ...
    • Centre for Digital Life Norway - Annual report 2017 

      Johansen, Finn-Eirik; Brautaset, Trygve; Aune, Marie Hjelmseth; Patriksson, Alexandra; Falkenberg, Liv Eggset; Kleppe, Rune; Dick, Gunnar; Strand, Berit Løkensgard; Eijsink, Vincent; Røyne, Anja; Goksøyr, Anders; Svendsen, John Sigurd Mjøen; Fyhn, Marianne; Vik, Jon Olav; Wentzel, Alexander; Aksnes, Astrid; Bruheim, Per; Carlsen, Sven Magnus; Åm, Heidrun (Research report, 2018)
    • Characterization of Solar Cell Wafers with Low Coherence Interferometry 

      Simonsen, Ove (Master thesis, 2011)
      Characterize silicon wafers used in solar cell production with a NIR-LCI interferometer. The interferometer is further developed and measurements on silicon samples are carried out.
    • Coupling of light from telescope into single mode fiber 

      Grønning, Knut Rudberg (Master thesis, 2006)
      A preliminary tip/tilt correction system was designed and implemented to demonstrate the principles of tip/tilt correction of a 633nm laser beam. Two mirrors mounted on one-axis rotation stages were used, one to simulate ...
    • Design, fabrication and characterisation of silicon nitride nanophotonic biosensor components 

      Knain, Idunn (Master thesis, 2016)
      This master thesis is dedicated to silicon photonic components; their design, fabrication and characterisation. Waveguides are the fundamental component in the new and exciting field of interferometric biosensors. Their ...
    • Fabrication of a Silicon Photonic Crystal Biosensor 

      Bolstad, Torstein (Master thesis, 2014)
      The research performed in the scope of the master project and described in this thesis is devoted to the study of a two dimensional photonic crystal biosensor in silicon. The band gap of hexagonal photonic crystal slab ...
    • Feasibility of supercontinuum sources for use in glucose sensing by absorption spectroscopy 

      Fuglerud, Silje Skeide; Milenko, Karolina Barbara; Ellingsen, Reinold; Aksnes, Astrid; Hjelme, Dag Roar (Journal article; Peer reviewed, 2019)
      Diabetes mellitus 1 requires tight control of the blood glucose levels to avoid harmful effects of either too high (hyperglycemia) or too low (hypoglycemia) blood sugar. Due to the availability of low-cost components, ...
    • Fiber optic probes for biomedical optical spectroscopy 

      Bru, Jørgen (Master thesis, 2008)
      Optical spectroscopy has been well validated by the physical sciences as a method to characterize chemical compositions in biological material. It has also showed promising to detect atherosclerotic plaques, which can form ...
    • Glucose sensing by absorption spectroscopy using lensed optical fibers 

      Fuglerud, Silje Skeide; Milenko, Karolina Barbara; Ellingsen, Reinold; Aksnes, Astrid; Hjelme, Dag Roar (Journal article; Peer reviewed, 2019)
      The bulkiness of common transmission spectroscopy probes prevents applicability at remote locations such as within the body. We present the fabrication and characterization of lensed fibers for transmission spectroscopy ...
    • Heterodyne interferometer for absolute amplitude vibration measurements with femtometer sensitivity 

      Leirset, Erlend; Engan, Helge Emil; Aksnes, Astrid (Journal article; Peer reviewed, 2013)
      A heterodyne interferometer for highly sensitive vibration measurements in the range 100kHz − 1.3GHz is presented. The interferometer measures absolute amplitude and phase. The signal processing of the setup is analyzed ...
    • High-concentration wide-angle tracking integration with stacked lens arrays 

      Johnsen, Håkon Jarand Dugstad; Aksnes, Astrid; Torgersen, Jan (Chapter, 2019)
      Tracking-integration can reduce or eliminate the need for external solar tracking in CPV (concentrator photovoltaics). Previous research has shown how tracking-integrated systems can achieve high concentration ratios, wide ...
    • Hyperspectral Analysis of Plastic Particles in the Ocean 

      Bogfjellmo, Silja (Master thesis, 2016)
      Huge amounts of plastics end up in the ocean each year. Some of the plastics are eaten by fish and birds, and can cause death. It is important to find an easy, fast and reliable method to detect the plastics, as a first ...
    • Hyperspectral imaging of atherosclerotic plaques in vitro 

      Larsen, Eivind La Puebla; Randeberg, Lise Lyngsnes; Olstad, Elisabeth; Haugen, Olav Anton; Aksnes, Astrid; Svaasand, Lars O. (Journal article; Peer reviewed, 2011)
      Vulnerable plaques constitute a risk for serious heart problems, and are difficult to identify using existing methods. Hyperspectral imaging combines spectral- and spatial information, providing new possibilities for precise ...
    • Infrared Spectroscopy with a Fiber-Coupled Quantum Cascade Laser for Attenuated Total Reflection Measurements Towards Biomedical Applications 

      Jernelv, Ine Larsen; Strøm, Karina; Hjelme, Dag Roar; Aksnes, Astrid (Journal article; Peer reviewed, 2019)
      The development of rapid and accurate biomedical laser spectroscopy systems in the mid-infrared has been enabled by the commercial availability of external-cavity quantum cascade lasers (EC-QCLs). EC-QCLs are a preferable ...
    • Investigation of methods for speckle contrast reduction 

      Welde, Kristine (Master thesis, 2010)
      Speckle arises when coherent light is reflected from a rough screen and observed by an intensity detector with a finite aperture. Because speckle causes serious image degradation when lasers are used as light sources in ...
    • Measurements of Optical Penetration Depth in Smoked Salmon 

      Johansen, Remi Andre Ursin (Master thesis, 2008)
      Optical spectroscopy is a common method used in the determination of quality parameters in groceries. An optical characterization of smoked Atlantic salmon was carried out in this thesis. The optical penetration depth in ...
    • Micro-lensed optical fibers for a surface-enhanced Raman scattering sensing probe 

      Milenko, Karolina Barbara; Fuglerud, Silje Skeide; Kjeldby, Snorre B; Ellingsen, Reinold; Aksnes, Astrid; Hjelme, Dag Roar (Journal article; Peer reviewed, 2018)
      We present the fabrication and characterization of a novel sensing configuration based on surface-enhanced Raman scattering (SERS) and two micro-lensed optical fibers. The first micro-lensed fiber is used to excite surface ...
    • Mid-Infrared Laser Spectroscopy for Glucose Sensing 

      Strøm, Karina (Master thesis, 2019)
      For å kunne lage en enhet for kontinuerlig glukosemåling som har lang levetid er det ønskelig med en forbedret spektroskopi målemetode for å kunne detektere glukose. En slik enhet vil kunne forbedre livskvaliteten til ...