@article {jaehne2015c,
	title = {The ocean in the lab: measurements with light and shadow},
	journal = {Ruperto Carola Forschungsmagazin Heidelberg University},
	volume = {7},
	year = {2015},
	pages = {52{\textendash}59},
	doi = {10.17885/heiup.ruca.23497},
	author = {Bernd J{\"a}hne}
}
@article {friedl2015,
	title = {Optical sensing of oxygen using a modified Stern-Volmer equation for high laser irradiance},
	journal = {Sensors and Actuators B: Chemical},
	volume = {206},
	year = {2015},
	pages = {336{\textendash}342},
	doi = {10.1016/j.snb.2014.09.073},
	author = {Felix Friedl and Nils Krah and Bernd J{\"a}hne}
}
@article {friedl2015,
	title = {Optical sensing of oxygen using a modified Stern-Volmer equation for high laser irradiance},
	journal = {Sensors and Actuators B: Chemical},
	volume = {206},
	year = {2015},
	note = {Available online 30 September 2014},
	pages = {336--342},
	doi = {10.1016/j.snb.2014.09.073},
	author = {Felix Friedl and Nils Krah and Bernd J{\"a}hne}
}
@conference {kiefhaber2013,
	title = {Optical measurement of surface ocean waves},
	booktitle = {3rd EOS Topical Meeting on Blue Photonics --- Optics in the Sea},
	year = {2013},
	note = {best student poster award},
	doi = {10.5281/zenodo.12334},
	author = {Daniel Kiefhaber and Roland Rocholz and Paulus Salomon Bauer and Bernd J{\"a}hne}
}
@article {atif2013,
	title = {Optimal Depth Estimation from a Single Image by Computational Imaging Using Chromatic Aberrations},
	journal = {tm --- Technisches Messen},
	volume = {80},
	year = {2013},
	pages = {343--348},
	abstract = {We present a computational imaging approach to estimate the depth from a single image using axial chromatic aberrations. It includes a co-design of optics and digital processing to select the optimal parameters of a lens such as focal length, f-number, and chromatic focal shift according to the performance of a depth estimation algorithm on the digital side. A simulation framework evaluates the complete systems performance in different imaging conditions including optimal axial chromatic lens aberration. A low-complexity algorithm estimates the depth map of real scenes. Experiments on real and synthetic scenes show the feasibility of the proposed system for depth estimation. In the case of relatively broadband object spectra and a lens with focal length of 4 mm, depth is estimated with an RMS error of 6{\textendash}10\%.},
	doi = {10.1515/teme.2013.0042},
	author = {Atif, Muhammad and Bernd J{\"a}hne}
}
@conference {mischler2012,
	title = {Optical measurements of bubbles and spray in wind/water facilities at high wind speeds},
	booktitle = {12th International Triennial Conference on Liquid Atomization and Spray Systems 2012, Heidelberg (ICLASS 2012)},
	year = {2012},
	abstract = {An optical imaging technique for the measurement of the size and velocity distribution of bubbles and droplets is presented. This method was used in a wind-wave tank at high wind-speeds to investigate bubble populations and spray generated by breaking water-waves. These measurements help to model bubble and spray induced gas exchange between atmosphere and ocean. The setup consists of a 2040  1088 CMOS-camera (Basler acA2000-340km, 5.5 mum pixel size), which is used in a telecentric bright-field setup. Thus bubbles or droplets between the light source and the camera become visible in the images as dark disks because of light scattering. For illumination, a single high-power LED (Cree XP-E) in a telecentric illumination system is used. This LED is operated in a pulsed mode with pulse lengths smaller than 2 mus. This is the effective exposure time. In order to acquire two images with a small temporal distance, the camera is set to maximal exposure time. The first image is recorded by flashing the LED at the end of the first exposure and the second image by flashing at the beginning of the second exposure. The effective time difference of consecutive exposures was between 1 mus and twice the exposure time of the camera. The telecentricity (only rays parallel to the optical axis contribute to the images) of the optics reduces the error of the size estimation of the bubbles/droplets. In addition the position along the optical axis can be estimated by a depth from defocus method. With this information it is also possible to determine the measuring volume to estimate the bubble/spray-number density. The size range of this technique is determined by the pixel and sensor size and by the resolution of the lens. Here, a lens with a working distance of 135 mm and a magnification of 0.37 is used, so that one pixel corresponds to 15 mum in object space. With this setup a radius range of 40 mum - 5000 mum can be imaged. The main source for the error of the radius is the blurring of the edges due to defocus. Therefore the accuracy depends on the quality of telecentricity and complexity of image processing. For bubbles with a radius larger than 10 px the error is below 1 \% when using simple image processing. This error can be reduced significantly by using elaborate image processing, which is also able to detect bubbles as small as 3 px in size. Different image processing algorithms for spherical objects are presented and investigated regarding accuracy. Bubbles or droplets which show deviation from sphere shape introduce problems for the image processing. For bubbles in still water, such deviations are typically found for radii of greater than 500 mum. Capabilities and limits of the technique are addressed on the example of two experiments. Test measurements were conducted at the high wind speed wind-wave tank in Kyoto, Japan at a wind speed of 42 m/s. This experiment showed that distributions of bubbles can be measured at high wind speeds with no problems in regions, which are not near to the water surface (> 2 cm). For regions close to the interface the image processing algorithms need to be adjusted, since portions of the illumination can be occluded by waves. It is shown with an experiment in the small linear wind/wave facility in Heidelberg, that this technique also works for spray measurements. Systematic measurements of spray could not be conducted in Kyoto, since the walls of the tank were covered by a thin film of water caused by the spray, which heavily disturbed the optical path.},
	doi = {10.5281/zenodo.10957},
	author = {Wolfgang Mischler and Bernd J{\"a}hne}
}
@article {jaehne2012b,
	title = {Optik, Photonik und Bildverarbeitung --- eine spannende Reise},
	journal = {Optik \& Photonik},
	volume = {7},
	number = {1},
	year = {2012},
	pages = {2--3},
	doi = {10.1002/opph.201290010},
	author = {Bernd J{\"a}hne}
}
@conference {atif2012,
	title = {Optimal Depth Estimation from a Single Image by Computational Imaging using Chromatic Aberrations},
	booktitle = {Forum Bildverarbeitung},
	year = {2012},
	pages = {23--34},
	publisher = {KIT Scientific Publishing},
	organization = {KIT Scientific Publishing},
	doi = {10.5445/KSP/1000030440},
	url = {http://digbib.ubka.uni-karlsruhe.de/volltexte/1000030440},
	author = {Atif, Muhammad and Bernd J{\"a}hne},
	editor = {F. Puente Leon and M. Heizmann}
}
@conference {erz2012,
	title = {Optimale und differenzierte Kameraauswahl nach dem EMVA-Standard 1288},
	booktitle = {Forum Bildverarbeitung},
	year = {2012},
	pages = {35--46},
	publisher = {KIT Scientific Publishing},
	organization = {KIT Scientific Publishing},
	doi = {10.5445/KSP/1000030440},
	url = {http://digbib.ubka.uni-karlsruhe.de/volltexte/1000030440},
	author = {Michael Erz and Bernd J{\"a}hne},
	editor = {F. Puente Leon and M. Heizmann}
}
@article {meister_12_outdoor,
	title = {Outdoor Stereo Camera System for the Generation of Real-World Benchmark
Data Sets},
	journal = {Optical Engineering},
	volume = {51},
	year = {2012},
	pages = {021107-1},
	doi = {10.1117/1.OE.51.2.021107},
	author = {Stephan Meister and Bernd J{\"a}hne and Daniel Kondermann}
}
@article {meister2012,
	title = {Outdoor stereo camera system for the generation of real-world benchmark data sets},
	journal = {Opt. Eng.},
	volume = {51},
	year = {2012},
	pages = {021107},
	doi = {10.1117/1.OE.51.2.021107},
	author = {Stephan Meister and Bernd J{\"a}hne and Daniel Kondermann}
}
@article {erz2011a,
	title = {Optimale Kameraauswahl f{\"u}r maschinelles Sehen durch standardisierte Charakterisierung},
	journal = {tm --- Technisches Messen},
	volume = {78},
	year = {2011},
	pages = {377--383},
	doi = {10.1524/teme.2011.0151},
	author = {Michael Erz and Bernd J{\"a}hne}
}
@conference {jehle_10_optimal,
	title = {Optimal Lighting for Defect Detection: Illumination Systems, Machine
Learning, and Practical Verification},
	booktitle = {Forum Bildverarbeitung, Regensburg, 02.-03.12.2010},
	year = {2010},
	note = {1},
	pages = {301-312},
	publisher = {KIT SCientific Publishing},
	organization = {KIT SCientific Publishing},
	author = {Markus Jehle and Bernd J{\"a}hne},
	editor = {F. Puente Leon and Heinzmann, M.}
}
@conference {jehle2010a,
	title = {Optimal lighting for defect detection: illumination systems, machine learning, and practical verification},
	booktitle = {Forum Bildverarbeitung},
	year = {2010},
	pages = {241--252},
	publisher = {KIT Scientific Publishing},
	organization = {KIT Scientific Publishing},
	url = {http://digbib.ubka.uni-karlsruhe.de/volltexte/1000020266},
	author = {Markus Jehle and Bernd J{\"a}hne},
	editor = {F. Puente Leon and M. Heizmann}
}
@conference {erz2010,
	title = {Optimierte Kameraauswahl f{\"u}r maschinelles Sehen durch standardisierte Charakterisierung des bildgebenden Systeme},
	booktitle = {Forum Bildverarbeitung},
	year = {2010},
	pages = {155--166},
	publisher = {KIT Scientific Publishing},
	organization = {KIT Scientific Publishing},
	url = {http://digbib.ubka.uni-karlsruhe.de/volltexte/1000020266},
	author = {Michael Erz and Bernd J{\"a}hne},
	editor = {F. Puente Leon and M. Heizmann}
}
@booklet {jaehne2009a,
	title = {Objektive Kriterien unterst{\"u}tzen die anwendungsorientierte Auswahl einer Kamera},
	year = {2009},
	note = {VDMA, Frankfurt},
	url = {http://www.vdma-verlag.com/home/p464.html},
	author = {Bernd J{\"a}hne}
}
@conference {mischler2009,
	title = {Optical method for measuring size-distribution and lifetime of bubbles},
	booktitle = {Poster abstracts SOLAS Open Science Conference, Barcelona, 16--19 Sep. 2009},
	year = {2009},
	abstract = {A high resolution imaging method for measuring the size distribution of bubbles entrained by water jets between 10-1000 um in diameter is presented. The bubble clouds are similar to those produced by breaking water waves. The goal of these measurements is the validation of models for bubble mediated gas transfer. A Depth from Focus technique is used to determine the 3D position and the size of the bubbles at the same time. This yields the size-distribution and its dependence on depth. Additionally the velocity of the bubbles is estimated using repeatedly exposed images. To evaluate the lifetime of bubbles a high-speed camera is used to count the bubbles crossing the surface. The measuring principle, image analysis and first results are presented.},
	author = {Wolfgang Mischler and Roland Rocholz and Bernd J{\"a}hne}
}
@article {garbe2008b,
	title = {An optical flow MTV based technique for measuring microfluidic flow in the presence of diffusion and Taylor dispersion},
	journal = {Exp. Fluids},
	volume = {44},
	year = {2008},
	pages = {439--450},
	abstract = {A novel technique is presented for accurately measuring flow fields in microfluidic flows from molecular tagging velocimetry (MTV). Limited optical access is frequently encountered in microfluidic systems. Therefore, in this contribution we analyze the special case of tagging a line across the thin dimension of a microchannel and subsequent imaging along this line. This represents a set-up that is applicable to a wide range of microfluidic applications. A volume illumination has to be used, resulting in an integration of the visualized dye across the flow profile. This leads to the well-known effect of Taylor dispersion. Our novel technique consists of measuring motion from digital image sequences in a gradient-based approach. A motion model is developed which explicitly deals with brightness changes due to Taylor dispersion and additional molecular diffusion of dyes. The presented approach is specific to the case of a parabolic velocity profile. In the presence of these effects, an accurate computation of motion is only possible by applying this novel motion model. Our technique is tested on simulated sequences corrupted with varying levels of noise and on actual measurements. Measurements were conducted in a microfluidic mixer of precisely known flow properties. In the same mixer, a comparative study of our MTV technique to uPIV was performed. Also, the results were compared to bulk measurements of the fluid flow velocity. The novel algorithm compared favorably and also, measurements were conducted on inhomogeneous flow configurations.},
	doi = {10.1007/s00348-007-0435-7},
	author = {Christoph S. Garbe and Karsten Roetmann and Volker Beushausen and Bernd J{\"a}hne}
}
@conference {garbe2006b,
	title = {An optical flow based technique for the non-invasive measurement of microfluidic flows},
	booktitle = {12th Intern. Symp. on Flow Visualization, G{\"o}ttingen, 10--14. September 2006},
	year = {2006},
	doi = {10.5281/zenodo.14846},
	author = {Christoph S. Garbe and Karsten Roetmann and Bernd J{\"a}hne}
}
@article {wenig2005,
	title = {Operator representation as a new differential optical absorption spectroscopy formalism},
	journal = {Appl. Optics},
	volume = {44},
	year = {2005},
	pages = {3246-3253},
	abstract = {UV-visible absorption spectroscopy with extraterrestrial light sources is a widely used technique for the measurement of stratospheric and tropospheric trace gases. We focus on differential optical absorption spectroscopy (DOAS) and present an operator notation as a new formalism to describe the different processes in the atmosphere and the simplifying assumptions that compose the advantage of DOAS. This formalism provides tools to classify and reduce possible error sources of DOAS applications.},
	doi = {10.1364/AO.44.003246},
	author = {Mark Wenig and Bernd J{\"a}hne and Ulrich Platt}
}
@conference {schimpf2003a,
	title = {Observational studies of parameters influencing air--sea gas exchange},
	booktitle = {Geophysical Research Abstracts},
	volume = {5},
	year = {2003},
	pages = {09328},
	author = {Uwe Schimpf and Nelson M. Frew and Kalkenings, R. and Christoph S. Garbe and Bernd J{\"a}hne}
}
@conference {bock2002,
	title = {Overview of the CoOP experiments: physical and chemical measurements parameterizing air-sea gas transfer},
	booktitle = {Gas Transfer at Water Surfaces},
	volume = {127},
	year = {2002},
	pages = {39--44},
	publisher = {American Geophysical Union},
	organization = {American Geophysical Union},
	doi = {10.1029/GM127p0039},
	author = {E. J. Bock and J. B. Edson and Nelson M. Frew and T. Hara and Horst Hau{\ss}ecker and Bernd J{\"a}hne and W. R. McGilles and S. P. McKenna and R. K. Nelson and Uwe Schimpf and B. M. Uz},
	editor = {M. A. Donelan and W. M. Drennan and R. Wanninkhof and E. S. Saltzman}
}
@incollection {huang2001,
	title = {Ocean wave spectra and integral properties},
	year = {2001},
	pages = {82--123},
	publisher = {Cambridge University Press},
	doi = {10.1017/CBO9780511552076.005},
	author = {N. E. Huang and Y. Toba and Z. Shen and J. Klinke and Bernd J{\"a}hne and M. L. Banner},
	editor = {I. S. F. Jones and Y Toba}
}
@incollection {schmundt2000,
	title = {Optical leaf growth analysis},
	year = {2000},
	pages = {640-641},
	publisher = {Academic Press},
	chapter = {A16},
	author = {Dominik Schmund and Ulrich Schurr and Bernd J{\"a}hne},
	editor = {Hau\DFecker, H.}
}
@conference {klinke1999,
	title = {Observations of free and bound gravity-capillary Waves},
	booktitle = {The Wind-Driven Air-Sea Interface, Electromagnetic and Acoustic Sensing, Wave Dynamics and Turbulent Fluxes},
	year = {1999},
	pages = {87--88},
	doi = {10.5281/zenodo.14908},
	author = {J. Klinke and Bernd J{\"a}hne and S. R. Long}
}
@conference {scheuermann1995,
	title = {Oberfl{\"a}chenkonturvermessung mikroskopischer Objekte durch Projektion statistischer Rauschmuster},
	booktitle = {Proc. 17. DAGM-Symposium Mustererkennung, Bielefeld, 13.-15. September 1995},
	year = {1995},
	pages = {319--326},
	author = {Scheuermann, T. and Pfundt, G. and Eyerer, P. and Bernd J{\"a}hne}
}
@conference {geissler1995a,
	title = {One-image depth-from-focus for concentration measurements},
	booktitle = {Proc. ISPRS Intercommission Workshop {\textquoteleft}From Pixels to Sequences{\textquoteright}, Zurich, March 22 - 24, 1995, In Int{\textquoteright}l Arch. of Photog. and Rem. Sens.},
	volume = {XXX-5W1},
	year = {1995},
	pages = {122--127},
	publisher = {RISC Books},
	organization = {RISC Books},
	doi = {10.5281/zenodo.14891},
	author = {Peter Gei{\ss}ler and Bernd J{\"a}hne},
	editor = {Baltsavias, E. P.}
}
@conference {jaehne1989d,
	title = {Optical measuring technique for small scale water surface waves},
	booktitle = {Advanced Optical Instrumentation for Remote Sensing of the Earth{\textquoteright}s Surface from Space, SPIE Proceeding 1129, International Congress on Optical Science and Engineering, Paris, 24-28 April 1989},
	year = {1989},
	pages = {147--152},
	doi = {10.1117/12.961496},
	author = {Bernd J{\"a}hne and Bernd J{\"a}hne},
	editor = {Stefan Waas and Stefan Waas}
}
@conference {jaehne1983a,
	title = {Optical water waves measuring techniques},
	booktitle = {Talk, 1st International Symposium on Gas Transfer at Water Surfaces, Cornell University, Ithaca, New York, June 13--15, 1983},
	year = {1983},
	doi = {10.5281/zenodo.14008},
	author = {Bernd J{\"a}hne}
}
