@misc{11595,
  abstract     = {{The ability to manufacture complex 3D-objects directly from its CAD model is the important reason why additive manufacturing is being widely used to fabricate cost-efficient prototypes and preferred over conventional manufacturing methods. Moreover, it portrays as a bridging technology to connect different scientific and industrial fields, e.g. Engineering, Medicine, etc. Consequently, additive manufacturing finds its applications in the production of patient-specific orthoses. This paper discusses the development of a pressure sensor based on an optical waveguide principle manufactured using stereolithography apparatus process to embed into a below-knee orthosis. For Orthopedic patients, the below-knee orthosis must be adjusted to the lower leg at regular intervals due to anthropometric changes in patient’s body to achieve proper mobility and correct load. Currently, this alteration relies on the patient’s estimation of support load which is only sub-optimal. Hence, the concept of developing an intelligent orthosis with a novel embedded optical system to monitor the exact support load at the neuralgic is proposed.}},
  author       = {{Shahane, Akshay Manoj and Shrotri, Abhijeet Narendra and Wittenbröker, Christian and Stübbe, Oliver}},
  booktitle    = {{3D Printed Optics and Additive Photonic Manufacturing IV}},
  editor       = {{von Freymann, Georg and Herkommer, Alois M. and Flury, Manuel}},
  isbn         = {{9781510673083}},
  issn         = {{1996-756X}},
  location     = {{Strasbourg}},
  publisher    = {{SPIE}},
  title        = {{{Manufacturing of solid core optical waveguide based pressure sensor for 3D-printed below-knee orthosis}}},
  doi          = {{10.1117/12.3016629}},
  volume       = {{12995}},
  year         = {{2024}},
}

@misc{7670,
  abstract     = {{Additive manufacturing (AM) and rapid prototyping process (RPP) have revolutionized the production of 3D objects in the last few decades. RPP has considerably increased the rate of production and the possibility of manufacturing prototypes in the fields of electrical, optical, and mechanical engineering. The manufacturing of optical prototypes including spherical, aspheric, and special kinds of lenses and lens arrays has reformed the fabrication of optical components. In this paper, specifically designed lens array prototypes for application in visible light communication (VLC) are introduced. These lens array prototypes are manufactured using the stereolithography apparatus (SLA) process. These lens arrays are designed to achieve optimal transmission of the light beam for VLC systems. One of the prototypes from the lens arrays contains primarily four spherical lenses and one thicker convex lens and the other contains one fresnel lens as a substitute for thicker convex lens. These lens arrays are further post-processed to achieve the required transparency. These lens array prototypes are tested using laser and LEDs. The ON-OFF keying modulated light beam was transmitted through the lens array at the sender side and focused on the photo-receiver using another lens array at the receiver side which is 200 cm apart. After evaluating these lens prototypes, it can be concluded that with appropriate post-processing and high-resolution stereolithography based manufacturing, a low data rate VLC link can be formed.}},
  author       = {{Shrotri, Abhijeet Narendra and Beyer, Micha and Schneider, Daniel Johann and Stübbe, Oliver}},
  booktitle    = {{Laser 3D Manufacturing VIII}},
  editor       = {{Helvajian, Henry and Gu, Bo and Chen, Hongqiang}},
  isbn         = {{978-1-5106-4189-1}},
  issn         = {{1996-756X}},
  keywords     = {{Additive manufacturing, 3D printing, Stereolithography apparatus, Spherical lenses, Fresnel lenses, Visible light communication}},
  location     = {{San Francisco }},
  publisher    = {{Society of Photo-Optical Instrumentation Engineers}},
  title        = {{{Manufacturing of lens array prototypes containing spherical and fresnel lenses for visible light communications using stereolithography apparatus}}},
  doi          = {{10.1117/12.2586907}},
  volume       = {{11677}},
  year         = {{2021}},
}

@inproceedings{7672,
  abstract     = {{Visible light communication (VLC) allows the dual use of lighting and wireless communication systems by
modulation of illumination devices. However, to increase the performance, typically, beam-forming measures are
taken creating pencil beams, thus contradicting the illumination purpose. In order to optimize the performance
trade o between ecient illumination and communication, the switching capabilities of illumination LEDs are
examined. Illumination LEDs with standard drivers and without beam-forming show limited applicability for
communication purposes as they are not optimized for the necessary switching capability (f  11 MHz) and
coherence. Methods to enhance the electrical current by pre-equalisation, biasing, carrier sweeping and current
shaping are examined in respect to the illumination LED's communication performance. A novel driver scheme
is derived which achieves considerably higher switching frequencies (f  100 MHz) without employing beamforming
at the illumination LED. This driver is able to obtain a data rate of up to 200 Mbit/s at a distance of
3.2 m, using on-o keying (OOK) modulation technique. Therefore, it is feasible to apply the LED driver by
implementing standardised illumination devices in VLC systems.}},
  author       = {{Schneider, Daniel and Shrotri, Abhijeet Narendra and Flatt, Holger and Stübbe, Oliver and Lachmayer, Roland}},
  booktitle    = {{Integrated Optics: Design, Devices, Systems and Applications VI}},
  editor       = {{Cheben, Pavel and Čtyroký, Jiří and Molina-Fernández, Iñigo}},
  isbn         = {{978-1-5106-4384-0}},
  issn         = {{1996-756X}},
  keywords     = {{Optical Wireless Communication, Visible Light Communication, VLC, Li-Fi, Illumination, Dual-purpose drivers}},
  location     = {{Online (Prag)}},
  publisher    = {{SPIE}},
  title        = {{{Efficient visible light communication drivers using illumination LEDs in industrial environments}}},
  doi          = {{10.1117/12.2588923}},
  volume       = {{11775}},
  year         = {{2021}},
}

@misc{7676,
  author       = {{Shrotri, Abhijeet Narendra and Beyer, Micha and Stübbe, Oliver}},
  booktitle    = {{3D Printed Optics and Additive Photonic Manufacturing II : 6-10 April 2020, online only, France }},
  editor       = {{von Freymann, Georg and Herkommer, Alois M. and Flury, Manuel}},
  isbn         = {{978-1-5106-3470-1}},
  issn         = {{1996-756X}},
  keywords     = {{Fresnel lenses, Stereolithography apparatus, 3D printing, Photo-polymerization}},
  location     = {{Strasbourg (online)}},
  publisher    = {{SPIE}},
  title        = {{{Manufacturing and analyzing of cost-efficient fresnel lenses using stereolithography}}},
  doi          = {{10.1117/12.2555367}},
  volume       = {{11349}},
  year         = {{2020}},
}

@misc{11134,
  author       = {{Stübbe, Oliver and Huxol, Andrea and Villmer, Franz-Josef}},
  booktitle    = {{3D Printed Optics and Additive Photonic Manufacturing}},
  editor       = {{von Freymann, Georg and Herkommer, Alois M. and Flury, Manuel}},
  issn         = {{1996-756X}},
  location     = {{Strasbourg, France}},
  publisher    = {{SPIE}},
  title        = {{{Applying fused layer modeling technologies to print embedded 3D optical waveguide structures for communication and sensor applications}}},
  doi          = {{10.1117/12.2306910}},
  volume       = {{10675}},
  year         = {{2018}},
}

@inproceedings{10226,
  abstract     = {{This paper presents a bidirectional optical data transmission system as an enhancement of a contactless power transmission system (CPTS). The latter consists of two separate devices and is able to transmit up to 240W of electrical power using inductive resonant coupling. The optical system consists of two self-developed light-guiding structures and a short-reach free-space optical path. As source and sink of the optical system a light-emitting diode resp. a photodiode with a centroid wavelength of 850nm are used. The optical system is positioned within the CPTS; it transmits the PROFIBUS protocol. Due to the restrictions given by the applications areas of the CPTS, such as air gap up to 5°mm, misalignment up to 2 mm, tilting up to 5 and rotation angle up to 360°, different kinds of light-guiding structures are analyzed by simulation. Based on these results the most promising structures are selected and manufactured. Hereafter the attenuation and the near field characteristic of one light-guiding structure is analyzed. After this, the attenuation based on misalignment, variation of air gap, tilting and rotation between two light-guiding structures are analyzed by measurement. To check whether the requirements of the PROFIBUS has been satisfied by the complete data transmission system, the transient transmission behavior of the system was analyzed by a pseudo-random bit stream. In this paper the most important results of the design, the simulation and the measurement are explained. The presented results demonstrate the ability to design of such systems based on simulations and to evaluate the suitability of various geometries for present and future works.}},
  author       = {{Neu, Marc and Grünberg, Olaf and Christophliemke, Tobias and Stübbe, Oliver}},
  booktitle    = {{Optical Interconnects XVII}},
  editor       = {{Schröder, Henning and Chen, Ray T.}},
  issn         = {{0277-786X}},
  location     = {{San Francisco}},
  publisher    = {{SPIE}},
  title        = {{{Modeling, simulation and measurement of a bidirectional optical interconnection system for industrial applications}}},
  doi          = {{10.1117/12.2251014}},
  volume       = {{10109}},
  year         = {{2017}},
}

@misc{7853,
  author       = {{Hennigs, Christian and Lahdo, Rabi and Springer, André and Kaierle, Stefan and Hustedt, Michael and Brand, Helmut and Wloka, Richard and Zobel, Frank and Dültgen, Peter}},
  booktitle    = {{SPIE Proceedings}},
  editor       = {{Dorsch, Friedhelm and Kaierle, Stefan}},
  issn         = {{0277-786X}},
  location     = {{San Francisco, California, United States}},
  publisher    = {{Society of Photo-Optical Instrumentation Engineers (SPIE)}},
  title        = {{{Laser-based gluing of diamond-tipped saw blades}}},
  doi          = {{10.1117/12.2212842}},
  year         = {{2016}},
}

@inproceedings{10224,
  abstract     = {{Optical interconnects on printed circuit board level are a promising choice to support high bandwidth for short distance interconnects. These interconnects consists of highly multimode step index waveguides with rectangular core cross sections. Therefore ray tracing is an excellent method to determine the optical path parameters, e.g. optical power, ray path lengths and local ray directions. Based on these parameters the step response, the transient transfer function and the coupling behavior can be calculated. Classical ray tracing methods calculates the optical path parameters of each ray by successively computing internal reflections until a termination condition is reached. Therefore the computing time depends on the number of internal reflections. If the optical waveguide consists of cascaded straight and curved segments, e. g. point-to-point interconnects, one can use the analytic ray tracing method to determine the optical path parameters. The whole path parameters of each ray are determined by one analytical computation. The computing time depends on the number of segments. The analytic ray tracing method is unusable to determine ray path parameters of segments with varying core cross sections, e.g. tapers, crossings, splitters and combiners.}},
  author       = {{Stübbe, Oliver}},
  booktitle    = {{Optical Interconnects XVII}},
  editor       = {{Schröder, Henning and Chen, Ray T.}},
  issn         = {{0277-786X}},
  location     = {{San Francisco}},
  publisher    = {{SPIE}},
  title        = {{{Semi-analytic ray tracing method for time-efficient computing of transmission behavior of PCB level optical interconnects with varying core cross sections}}},
  doi          = {{10.1117/12.2076931}},
  volume       = {{9368}},
  year         = {{2015}},
}

@misc{7863,
  author       = {{Schimek, Mitja and Springer, André and Pfeifer, Ronny and Kaierle, Stefan}},
  booktitle    = {{SPIE Proceedings}},
  editor       = {{Dorsch, Friedhelm}},
  issn         = {{0277-786X}},
  location     = {{San Francisco, California, United States}},
  publisher    = {{SPIE}},
  title        = {{{Laser welding of dissimilar materials for lightweight construction and special applications}}},
  doi          = {{10.1117/12.2006335}},
  year         = {{2013}},
}

@misc{11230,
  abstract     = {{A Proof-of-Concept for a multi-channel WDM board-level optical communications link is under development. This paper is focusing on theoretical and experimental evaluation of thin-glass based nearly single mode graded index optical waveguides with regard to low loss in the 1310nm regime. Results from waveguide characterization will be reported. Waveguide modes are determined theoretically from the measured refractive index profiles. Towards improvement of the robustness of the coupling efficiency against misalignments, investigations on the use of tapered waveguide structures will be presented too.}},
  author       = {{Schrage, J. and Stübbe, Oliver and Brusberg, L. and Soenmez, Y. and Schroeder, H. and Schuhmann, R.}},
  booktitle    = {{Optoelectronic Interconnects and Component Integration XI}},
  editor       = {{Glebov, Alexei L. and Chen, Ray T.}},
  isbn         = {{ 978-0-8194-8481-9 }},
  issn         = {{0277-786X}},
  location     = {{San Francisco, California, United States}},
  publisher    = {{SPIE}},
  title        = {{{Evaluation of graded index glass waveguides for board-level WDM optical chip-to-chip communications}}},
  doi          = {{10.1117/12.876458}},
  volume       = {{7944}},
  year         = {{2011}},
}

@misc{11130,
  abstract     = {{Modal noise is an undesired modulation of the guided light intensity in a multimode waveguide. Applying the frequency correlation function the frequency dependence of this noise as well as the bandwidth of a multimode waveguide can be estimated. In this paper the existing model of the frequency correlation function for a waveguide with smoothed dielectric interfaces is enhanced to analyze the influence of surface roughness on the achievable bandwidth. This surface roughness is caused by the manufacturing process of the waveguides.}},
  author       = {{Stübbe, Oliver and Bierhoff, Thomas and Schrage, Juergen and Mrozynski, Gerd}},
  booktitle    = {{Wave Optics and Photonic Devices for Optical Information Processing II}},
  editor       = {{Ambs, Pierre and Beyette, Jr., Fred R.}},
  issn         = {{0277-786X}},
  location     = {{San Diego, California, United States}},
  publisher    = {{SPIE}},
  title        = {{{Influence of surface roughness on the bandwidth of optical multimode waveguides analyzed by modal noise theory}}},
  doi          = {{10.1117/12.505775}},
  volume       = {{5181}},
  year         = {{2003}},
}

@misc{11201,
  abstract     = {{Modal noise is an undesired modulation of the guided light intensity in a multimode waveguide. Applying the frequency correlation function the frequency dependence of this noise as well as the bandwidth of a multimode waveguide can be estimated. In this paper the existing model of the frequency correlation function for a waveguide with smoothed dielectric interfaces is enhanced to analyze the influence of surface roughness on the achievable bandwidth. This surface roughness is caused by the manufacturing process of the waveguides.}},
  author       = {{Stübbe, Oliver and Bierhoff, Thomas and Schrage, Juergen and Mrozynski, Gerd}},
  booktitle    = {{Wave Optics and Photonic Devices for Optical Information Processing II}},
  editor       = {{Ambs, Pierre and Beyette, Jr., Fred R.}},
  isbn         = {{0-8194-5054-5 }},
  issn         = {{0277-786X}},
  location     = {{San Diego, California, United States}},
  publisher    = {{SPIE}},
  title        = {{{Influence of surface roughness on the bandwidth of optical multimode waveguides analyzed by modal noise theory}}},
  doi          = {{10.1117/12.505775}},
  volume       = {{5181}},
  year         = {{2003}},
}