Prof. Bernd Jähne Profile

Prof. Bernd Jähne

Senior Professor at Heidelberg University, IWR

SPIE Involvement:

Author

Proceedings Article | 12 August 2023 Presentation

A multi-camera and multi-illumination system for combined measurements of mass exchange and waves at a wind-driven water surface

Bernd Jähne, Dennis Hofmann

Proceedings Volume 12623, 1262303 (2023) https://doi.org/10.1117/12.2674824

KEYWORDS: Semiconductor lasers, Fluorescence, Cameras, Windows, Solubility, Holography, Gases, Dyes, Chemical species

Read Abstract +

Proceedings Article | 12 August 2023 Presentation

Thermographic imaging of shear flow at a wind-driven water surface

Bernd Jähne, Sebastian Leyer, Roman Stewing, Kerstin Krall

Proceedings Volume 12623, 1262302 (2023) https://doi.org/10.1117/12.2674816

KEYWORDS: Thermography, Diffusion, Optical flow, Motion measurement, Motion estimation, Modulation, Laser irradiation, Inspection, Heat flux, Fiber lasers

Read Abstract +

Proceedings Article | 21 June 2015 Paper

Light-field camera design for high-accuracy depth estimation

M. Diebold, O. Blum, M. Gutsche, S. Wanner, C. Garbe, H. Baker, B. Jähne

Proceedings Volume 9528, 952803 (2015) https://doi.org/10.1117/12.2184845

KEYWORDS: Cameras, Calibration, Imaging systems, Image resolution, Distance measurement, Error analysis, Clouds, 3D image processing, Range imaging, Objectives

Read Abstract +

SPIE Journal Paper | 7 March 2012

Outdoor stereo camera system for the generation of real-world benchmark data sets

Stephan Meister, Bernd Jaehne, Daniel Kondermann

OE, Vol. 51, Issue 02, 021107, (March 2012) https://doi.org/10.1117/12.10.1117/1.OE.51.2.021107

KEYWORDS: Cameras, Imaging systems, Stereoscopic cameras, Image processing, Calibration, Global Positioning System, Sensors, Light sources and illumination, Optical flow, Optical engineering

Read Abstract +

Proceedings Article | 6 May 2010 Paper

Multi-frequency multi-sampling fluorescence lifetime imaging using a high speed line-scan camera

Zhuang Lin, Michael Erz, Bernd Jähne

Proceedings Volume 7723, 77231S (2010) https://doi.org/10.1117/12.854763

KEYWORDS: Modulation, Phase shift keying, Luminescence, Monte Carlo methods, Cameras, Signal to noise ratio, Fluorescence lifetime imaging, Line scan image sensors, Imaging systems, Signal processing

Read Abstract +

SPIE Journal Paper | 1 January 2009

Theoretical and experimental error analysis of continuous-wave time-of-flight range cameras

Mario Frank, Matthias Plaue, Holger Rapp, Ullrich Koethe, Bernd Jähne, Fred Hamprecht

OE, Vol. 48, Issue 01, 013602, (January 2009) https://doi.org/10.1117/12.10.1117/1.3070634

KEYWORDS: Cameras, Modulation, Quantization, Continuous wave operation, Error analysis, Optical engineering, Phase shift keying, Reflectivity, Sensors, Statistical analysis

Read Abstract +

Proceedings Article | 27 April 2006 Paper

One-shot line-profiling white light interferometer with spatial phase shift for measuring rough surfaces

M. Hering, S. Herrmann, M. Banyay, K. Körner, B. Jähne

Proceedings Volume 6188, 61880E (2006) https://doi.org/10.1117/12.662322

KEYWORDS: Sensors, Modulation transfer functions, Interferometers, Molybdenum, Phase shifts, Inspection, Mirrors, Visibility, Optical interferometry, Light sources

Read Abstract +

Proceedings Article | 1 April 2003 Paper

Estimation of complex motion from thermographic image sequences

Christoph Garbe, Hagen Spies, Bernd Jaehne

Proceedings Volume 5073, (2003) https://doi.org/10.1117/12.501121

KEYWORDS: Optical flow, Motion estimation, Motion models, Diffusion, Thermography, Image processing, Thermal modeling, Infrared imaging, Machine vision, Computer vision technology

Read Abstract +

SPIE Journal Paper | 1 January 2003 Open Access

Spatiotemporal anisotropic diffusion filtering to improve signal-to-noise ratios and object restoration in fluorescence microscopic image sequences

Dietmar Uttenweiler, Cornelia Weber, Bernd Jaehne, Rainer Fink, Hanno Scharr

JBO, Vol. 8, Issue 01, (January 2003) https://doi.org/10.1117/12.10.1117/1.1527627

KEYWORDS: Anisotropic diffusion, Anisotropic filtering, Image filtering, Luminescence, Diffusion, Signal to noise ratio, 3D image processing, Image processing, Nonlinear filtering, Smoothing

DOWNLOAD PAPER

Proceedings Article | 15 March 2002 Paper

Thermographic measurements on plant leaves

Christoph Garbe, Ulrich Schurr, Bernd Jaehne

Proceedings Volume 4710, (2002) https://doi.org/10.1117/12.459590

KEYWORDS: Thermography, Heat flux, Infrared cameras, Infrared radiation, Infrared imaging, Velocity measurements, Cameras, Temporal resolution, Temperature metrology, Physiology

Read Abstract +

Proceedings Article | 15 March 2002 Paper

Measuring important parameters for air-sea heat exchange

Christoph Garbe, Uwe Schimpf, Bernd Jaehne

Proceedings Volume 4710, (2002) https://doi.org/10.1117/12.459564

KEYWORDS: Heat flux, Statistical analysis, Infrared imaging, Infrared cameras, Temperature metrology, Meteorology, Thermal modeling, Cameras, Interfaces, Infrared radiation

Read Abstract +

The heat transfer between the ocean and the atmosphere is one of the most important parameters governing the global climate. Important parameters include the heat transfer velocity and the net heat flux as well as parameters of the underlying transport model. However, the net heat flux is hard to measure since processes take place in the thermal boundary layer, that is the topmost layer of the ocean less than 1 mm thick. Current techniques rely on three independent measurements of the constituent fluxes, the sensible heat flux, latent heat flux and radiative flux. They depend on indirect measurements of meteorological parameters and rely on a combination of data from different sensors using a number of heuristic assumptions. High relative errors and the need for long temporal averaging reduce the practicability of these techniques. In this paper a novel technique is presented that circumvents these drawbacks by directly measuring the net heat flux across the air-water interface with a single low-NETD infrared camera. A newly developed digital image processing technique allows to simultaneously estimating the surface velocity field and parameters of the temporal temperature change. In particular, this technique allows estimating the total derivative of the temperature with respect to time from a sequence of infrared images, together with error bounds on the estimates. This derivative can be used to compute the heat flux density and the heat transfer velocity, as well as the probability density function of the underlying surface renewal model. It is also possible to estimate the bulk-skin temperature difference given rise to by the net heat flux. Our technique has been successfully used in both laboratory measurements in the Heidelberg Aeolotron, as well as in field measurements in the equatorial pacific during the NOAA GasExII experiment this spring. The data show that heat flux measurements to an accuracy of better than 5% on a time scale of seconds are feasible.

Proceedings Article | 22 December 1992 Paper

Combined slope-height measurements of short wind waves: first results from field and laboratory measurements

Stefan Waas, Bernd Jaehne

Proceedings Volume 1749, (1992) https://doi.org/10.1117/12.138858

KEYWORDS: Wind measurement, Cameras, Radar, Interfaces, Algorithm development, Image processing, Light sources, Ocean optics, Capillaries, Sensors

Read Abstract +

Proceedings Article | 22 December 1992 Paper

Critical theoretical review of optical techniques for short-ocean-wave measurements

Bernd Jaehne, Stefan Waas, Jochen Klinke

Proceedings Volume 1749, (1992) https://doi.org/10.1117/12.138849

KEYWORDS: Water, Reflection, Light sources, Cameras, Ocean optics, Refraction, Machine vision, Computer vision technology, Interfaces, Image resolution

Read Abstract +