Dr. Thomas Klotzbücher Profile

Dr. Thomas Klotzbücher

at Fraunhofer ICT-IMM

SPIE Involvement:

Author

Publications (22)

Proceedings Article | 8 May 2014 Paper

In vivo continuous glucose monitoring using a chip based near infrared sensor

L. Ben Mohammadi, S. Sigloch, I. Frese, K. Welzel, M. Göddel, T. Klotzbücher

Proceedings Volume 9129, 912929 (2014) https://doi.org/10.1117/12.2052216

KEYWORDS: Sensors, Glucose, Blood, Infrared sensors, Near infrared, Polymers, Light emitting diodes, Microfluidics, In vivo imaging, Calibration

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Proceedings Article | 8 May 2012 Paper

A minimally invasive chip based near infrared sensor for continuous glucose monitoring

L. Ben Mohammadi, S. Sigloch, I. Frese, V. Stein, K. Welzel, F. Schmitz, T. Klotzbücher

Proceedings Volume 8427, 84270K (2012) https://doi.org/10.1117/12.922381

KEYWORDS: Glucose, Sensors, Light sources, Light emitting diodes, Spectroscopy, Absorbance, Near infrared, Microfluidics, Absorption, Signal to noise ratio

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Assessment of glycaemia in diabetes is crucially important for prevention of both, acute and long term complications. Continuous glucose monitoring (CGM) is certainly the most appropriate way for optimizing the glycaemic control, since it prevents or delays the progression of complications associated with hypo- or hyperglycaemic events, reducing morbidity, mortality, and overall costs in health care systems. In this paper we describe the concept and first in vitro results of a minimally invasive, chip-based NIR-Sensor for continuous glucose monitoring. The sensor concept is based on difference infrared absorption spectroscopy, which was evaluated within laboratory measurements of D+-Glucose dissolved in water. The laboratory measurements revealed a linear relationship between glucose concentration and the integrated difference spectroscopy signal with a coefficient of determination of 99.6% in the concentration range of 0- 500 mg/dL. Suitable wavelength bands were identified in which the correlation is preserved and commercial light sources are available for realisation of a spectrometer-less, integrated NIR-sensor. In the designed sensor the component area (non-disposable) is separated from the detection area (disposable, low-cost). The disposable part of the sensor is fluidically connected to a micro-dialyses needle, accessing glucose subcutaneously via the ISF (interstitial fluid) or intravascularly. The non-disposable part contains all the optical elements, like LED´s and photo-detectors. The in- and out-coupling of the optical signal is achieved across the plane of the chip by using total internal reflection on mirrors integrated into the fluidic chip. The glucose is continuously measured by considering the difference signals of light at the corresponding wavelengths, as a function of time or in defined intervals if the light sources are modulated. The in-vitro measurements show an absolute error of about 5 mg/dL with a relative error of 5% for glucose concentrations larger than 50 mg/dL and about 12 % in the hypoglycemic range (<50 mg /dL).

Proceedings Article | 22 February 2012 Paper

Nano-structured surfaces by laser interference lithography and fs-laser direct writing as substrates for surface-enhanced Raman spectroscopy

L. Ben Mohammadi, N. Hundertmark, F. Kullmann, F. Fleissner, T. Klotzbücher

Proceedings Volume 8244, 82440D (2012) https://doi.org/10.1117/12.906323

KEYWORDS: Raman spectroscopy, Surface enhanced Raman spectroscopy, Silver, Lithography, Metals, Spectroscopy, Molecules, Semiconductor lasers, Nanostructuring, Surface plasmons

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Proceedings Article | 14 May 2010 Paper

A low cost mid-infrared sensor for on line contamination monitoring of lubricating oils in marine engines

L. Ben Mohammadi, F. Kullmann, M. Holzki, S. Sigloch, T. Klotzbuecher, J. Spiesen, T. Tommingas, P. Weismann, G. Kimber

Proceedings Volume 7726, 77260M (2010) https://doi.org/10.1117/12.854476

KEYWORDS: Sensors, Absorbance, Calibration, Contamination, Water, Ocean optics, Signal detection, Absorption, Mid-IR, Infrared sensors

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The chemical and physical condition of oils in marine engines must be monitored to ensure optimum performance of the engine and to avoid damage by degraded oil not adequately lubricating the engine. Routine monitoring requires expensive laboratory testing and highly skilled analysts. This work describes the adaptation and implementation of a mid infrared (MIR) sensor module for continued oil condition monitoring in two-stroke and four-stroke diesel engines. The developed sensor module will help to reduce costs in oil analysis by eliminating the need to collect and send samples to a laboratory for analysis. The online MIR-Sensor module measures the contamination of oil with water, soot, as well as the degradation indicated by the TBN (Total Base Number) value. For the analysis of water, TBN, and soot in marine engine oils, four spectral regions of interest have been identified. The optical absorption in these bands correlating with the contaminations is measured simultaneously by using a four-field thermopile detector, combined with appropriate bandpass filters. Recording of the MIR-absorption was performed in a transmission mode using a flow-through cell with appropriate path length. Since in this case no spectrometer is required, the sensor including the light source, the flowthrough- cell, and the detector can be realised at low cost and in a very compact manner. The optical configuration of the sensor with minimal component number and signal intensity optimisation at the four-field detector was implemented by using non-sequential ray tracing simulation. The used calibration model was robust enough to predict accurately the value for soot, water, and TBN concentration for two-stroke and four-stroke engine oils. The sensor device is designed for direct installation on the host engine or machine and, therefore, becoming an integral part of the lubrication system. It can also be used as a portable stand-alone system for machine fluid analysis in the field.

Proceedings Article | 23 February 2010 Paper

Fabrication of micro-lenses using excimer laser ablation by means of laser-generated grey-tone-masks

T. Klotzbuecher, D. Dadic

Proceedings Volume 7585, 75850C (2010) https://doi.org/10.1117/12.845476

KEYWORDS: Laser ablation, Excimer lasers, Polymethylmethacrylate, Chromium, Objectives, Polymers, Computer programming, Photomasks, Diffraction, Mask making

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Proceedings Article | 23 February 2010 Paper

Fabrication of dielectric and metallo-dielectric 3D nanostructures by direct laser writing and electroless plating

André Radke, Frank Wolff, Harald Giessen, Thomas Klotzbücher

Proceedings Volume 7585, 75850M (2010) https://doi.org/10.1117/12.845474

KEYWORDS: Multiphoton lithography, Photonic crystals, Dielectrics, Electroless plating, Silver, Metals, Nanolithography, Microscopes, Photoresist materials, Absorption

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Proceedings Article | 24 February 2009 Paper

Active integrated components for fluid control in automatic analytical chip-based systems

F. von Germar, J. Claußen, R. Gransee, E. Schaeffer, L. Mohammadi, T. Klotzbücher

Proceedings Volume 7207, 720709 (2009) https://doi.org/10.1117/12.812012

KEYWORDS: Sensors, Prisms, Light emitting diodes, Microfluidics, Liquids, Light sources, Fiber couplers, Control systems, Modulation, Photodiodes

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Proceedings Article | 14 May 2008 Paper

Integrated optical sensor for liquid control in micro-fluidic channel systems

Frithjof v. Germar, Thomas Klotzbücher, Lhoucine Ben Mohammadi, Jan Claussen

Proceedings Volume 6992, 69920K (2008) https://doi.org/10.1117/12.784138

KEYWORDS: Sensors, Prisms, Liquids, Light emitting diodes, Microfluidics, Polymers, Water, Reflection, Control systems, Light sources

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Proceedings Article | 23 February 2008 Paper

Nano-structuring of polymer surfaces by multibeam laser interference for application in microfluidics

T. Klotzbuecher, A. Radke, A. Tunayar, O. Haverbeck, E. Weinbender, J. Wuesten, A. Toufali, J. Claussen, P. Detemple

Proceedings Volume 6880, 68800F (2008) https://doi.org/10.1117/12.768348

KEYWORDS: Polymers, Gold, Lithography, Liquids, Polymethylmethacrylate, Surface finishing, Scanning electron microscopy, Microfluidics, Solids, Staring arrays

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Proceedings Article | 23 February 2006 Paper

Diode laser welding for packaging of transparent micro-structured polymer chips

T. Klotzbuecher, M. Letschert, T. Braune, K.-S. Drese, T. Doll

Proceedings Volume 6107, 610704 (2006) https://doi.org/10.1117/12.649248

KEYWORDS: Absorption, Polymers, Polymethylmethacrylate, Laser welding, Semiconductor lasers, Coating, Interfaces, Image processing, Glasses, Packaging

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Proceedings Article | 10 September 2004 Paper

Investigations on 4x4 polymer couplers for airborne environment

Thomas Klotzbuecher, M. Sprzagala, Anne Koch, Ulrich Teubner

Proceedings Volume 5465, (2004) https://doi.org/10.1117/12.543389

KEYWORDS: Polymers, Humidity, Packaging, Glasses, Ceramics, Metals, Waveguides, Optical fibers, Optics manufacturing, Polymethylmethacrylate

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Proceedings Article | 18 August 2004 Paper

Hybrid 1x2 WDM components based on polymer mountings

Thomas Klotzbuecher, M. Sprzagala, Anne Koch, Ulrich Teubner

Proceedings Volume 5451, (2004) https://doi.org/10.1117/12.543387

KEYWORDS: GRIN lenses, Lens design, Optical filters, Wavelength division multiplexing, Lenses, Polymers, Optical components, Tolerancing, Polymethylmethacrylate, Ray tracing

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Proceedings Article | 16 August 2004 Paper

Polymer-based pixel matrix display in MOEMS technology

Ryszard Buczynski, Stefan Kufner, Rafal Kasztelanic, Arkadiusz Sagan, Ines Frese, Thomas Klotzbucher, Tomasz Szoplik

Proceedings Volume 5455, (2004) https://doi.org/10.1117/12.548753

KEYWORDS: Laser ablation, Polymers, Microopto electromechanical systems, Electrodes, Polymethylmethacrylate, Light emitting diodes, LCDs, Information visualization, Switching, Projection systems

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Proceedings Article | 9 June 2004 Paper

Laser-machined fibres as ultraminiature pressure sensors

Stuart Watson, Matthew Gander, William MacPherson, James Barton, Julian Jones, Thomas Klotzbuecher, Torsten Braune, Johannes Ott, Felix Schmitz

Proceedings Volume 5502, (2004) https://doi.org/10.1117/12.566532

KEYWORDS: Sensors, Fiber lasers, Fiber optics sensors, Fabry–Perot interferometers, Silicon, Epoxies, Optical fibers, Laser ablation, Polymers, Aerodynamics

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Proceedings Article | 15 April 2003 Paper

Fabrication of optical 1x2 POF couplers using the laser-LIGA technique

Thomas Klotzbuecher, Torsten Braune, Dalibor Dadic, M. Sprzagala, Anne Koch

Proceedings Volume 4941, (2003) https://doi.org/10.1117/12.470165

KEYWORDS: Phase only filters, Waveguides, Laser ablation, Light scattering, Fabrication, Ray tracing, Polymethylmethacrylate, Polymers, Polishing, Scattering

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Proceedings Article | 17 January 2003 Paper

Plastic micro-optical components with LIGA technology

Laurence Singleton, Peter Detemple, I. Frese, Thomas Klotzbuecher, Hans-Dieter Bauer

Proceedings Volume 4984, (2003) https://doi.org/10.1117/12.499993

KEYWORDS: Photomasks, Waveguides, X-rays, Manufacturing, Polymers, Structured optical fibers, Lithography, X-ray lithography, Optical alignment, Polymethylmethacrylate

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Proceedings Article | 29 June 2001 Paper

Polymer microsystems by excimer laser ablation: from rapid prototyping to large-number fabrication

Thomas Klotzbuecher, Torsten Braune, Susanne Sigloch, Jens Hossfeld, Michel Neumeier, Hans-Dieter Bauer, Wolfgang Ehrfeld

Proceedings Volume 4274, (2001) https://doi.org/10.1117/12.432523

KEYWORDS: Laser ablation, Excimer lasers, Polymers, Switches, Rapid manufacturing, Prototyping, Polymethylmethacrylate, Fabrication, Titanium, Pulsed laser operation

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Proceedings Article | 29 June 2001 Paper

PLD of hard ceramic coatings

Yibran Perera, Jens Gottmann, Andreas Husmann, Thomas Klotzbuecher, Ernst-Wolfgang Kreutz, Reinhart Poprawe

Proceedings Volume 4274, (2001) https://doi.org/10.1117/12.432550

KEYWORDS: Particles, Raman spectroscopy, Thin films, Refractive index, Chemical species, Ions, Polymethylmethacrylate, Molecules, Ceramics, Electroluminescence

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Proceedings Article | 7 June 2000 Paper

Custom specific fabrication of integrated optical devices by excimer laser ablation of polymers

Thomas Klotzbuecher, Martin Popp, Torsten Braune, Jens Haase, Anne Gaudron, Ingo Smaglinski, Thomas Paatzsch, Hans-Dieter Bauer, Wolfgang Ehrfeld

Proceedings Volume 3933, (2000) https://doi.org/10.1117/12.387565

KEYWORDS: Laser ablation, Polymers, Waveguides, Polymethylmethacrylate, Excimer lasers, Rapid manufacturing, Integrated optics, Surface roughness, Wave propagation, Optical components

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Proceedings Article | 26 May 1998 Paper

Raman spectroscopy on BaTiO3 ferroelectric thin films deposited by a hybrid DC-field-enhanced PLD process

Thomas Klotzbuecher, M. Mergens, Andreas Husmann, Jens Gottmann, Ernst-Wolfgang Kreutz

Proceedings Volume 3404, (1998) https://doi.org/10.1117/12.308635

KEYWORDS: Ferroelectric materials, Raman spectroscopy, Crystals, Thin films, Dielectrics, Plasma, Laser crystals, Phonons, Pulsed laser deposition, Atmospheric plasma

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Proceedings Article | 26 May 1998 Paper

DLC thin film growth under energetic particle bombardment: a comparison between PLD and rf-bias enhanced PLD

Thomas Klotzbuecher, Jens Gottmann, M. Meyer, David Wesner, Ernst-Wolfgang Kreutz

Proceedings Volume 3404, (1998) https://doi.org/10.1117/12.308599

KEYWORDS: Ions, Raman spectroscopy, Particles, Carbon, Laser processing, Pulsed laser deposition, Laser bonding, Chemical species, Thin film growth, Electrodes

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Proceedings Article | 26 May 1998 Paper

Growth of ceramic thin films by pulsed laser deposition: the role of the kinetic energy of laser-ablated particles

Jens Gottmann, Thomas Klotzbuecher, Ernst-Wolfgang Kreutz

Proceedings Volume 3404, (1998) https://doi.org/10.1117/12.308606

KEYWORDS: Particles, Thin films, Dielectrics, Ferroelectric materials, Refractive index, Pulsed laser deposition, Zirconium dioxide, Barium, Oxygen, Molecules

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