@article{HassMuenzbergBresseletal.2013,
  author    = {Hass, Roland and M{\"u}nzberg, Marvin and Bressel, Lena and Reich, Oliver},
  title     = {Industrial applications of photon density wave spectroscopy for in-line particle sizing [Invited]},
  series = {Applied optics},
  volume    = {52},
  journal   = {Applied optics},
  number    = {7},
  publisher = {Optical Society of America},
  address   = {Washington},
  issn      = {1559-128X},
  doi       = {10.1364/AO.52.001423},
  pages     = {1423 -- 1431},
  year      = {2013},
  abstract  = {Optical spectroscopy in highly turbid liquid material is often restricted by simultaneous occurrence of absorption and scattering of light. Photon Density Wave (PDW) spectroscopy is one of the very few, yet widely unknown, technologies for the independent quantification of these two optical processes. Here, a concise overview about modern PDW spectroscopy is given, including all necessary equations concerning the optical description of the investigated material, dependent light scattering, particle sizing, and PDW spectroscopy itself. Additionally, it is shown how the ambiguity in particle sizing, arising from Mie theory, can be correctly solved. Due to its high temporal resolution, its applicability to highest particle concentrations, and its purely fiber-optical probe, PDW spectroscopy possesses all fundamental characteristics for optical in-line process analysis. Several application examples from the chemical industry are presented. (C) 2013 Optical Society of America},
  language  = {en}
}
@article{BeschererMunzkeReichetal.2013,
  author    = {Bescherer, Klaus and Munzke, Dorit and Reich, Oliver and Loock, Hans-Peter},
  title     = {Fabrication and modeling of multimode fiber lenses},
  series = {Applied optics},
  volume    = {52},
  journal   = {Applied optics},
  number    = {4},
  publisher = {Optical Society of America},
  address   = {Washington},
  issn      = {1559-128X},
  doi       = {10.1364/AO.52.000B40},
  pages     = {B40 -- B45},
  year      = {2013},
  abstract  = {We report on the fabrication, modeling, and experimental verification of the emission of fiber lenses fabricated on multimode fibers in different media. Concave fiber lenses with a radius of 150 mu m were fabricated onto a multimode silica fiber (100 mu m core) by grinding and polishing against a ruby sphere template. In our theoretical model we assume that the fiber guides light from a Lambertian light source and that the emission cone is governed solely by the range of permitted emission angles. We investigate concave and convex lenses at 532 nm with different radii and in a variety of surrounding media from air (n(0) = 1.00) to sapphire (n(0) = 1.77). It was found that noticeable focusing or defocusing effects of a silica fiber lens in ethanol (n(0) = 1.36) and dimethyl sulfoxide (DMSO) (n(0) = 1.48) are only observed when the fiber lens radius was less than the fiber diameter.},
  language  = {en}
}