@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}},
}

@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{7679,
  author       = {{Shrotri, Abhijeet Narendra and Beyer, Micha and Stübbe, Oliver}},
  booktitle    = {{	 Production engineering and management : proceedings 9th international conference, October 03 and 04, 2019, Trieste, Italy}},
  editor       = {{Padoano, Elio and Villmer, Franz-Josef}},
  isbn         = {{978-3-946856-04-7}},
  keywords     = {{3D printing, stereolithography, optical lens, light forming structures, convex lenses, concave lenses, refraction of light, focal length}},
  location     = {{Trieste}},
  pages        = {{227--240}},
  publisher    = {{Technische Hochschule Ostwestfalen-Lippe}},
  title        = {{{Evaluation of stereolithograghy processes for the production of lens prototypes}}},
  volume       = {{2019, 01}},
  year         = {{2019}},
}

@inproceedings{585,
  abstract     = {{Many low-cost 3D printers have been brought to market over the last couple of years. Most of them apply a Fused Layer Manufacturing (FLM) process, and have made 3D printing a great success amongst hobbyists, the maker community and students. One drawback of such inexpensive equipment is a limited build envelope, which prevents this from becoming a significant contributor to industrial production. To overcome these limits, it is not sufficient to simply upscale dimensions, but the overall concept of such machines must be completely re-thought, as well as the concepts behind several building blocks, components and the process software system.
Problems such as shrinkage of build material, support material and machine parts in combination with long printer head travels, temperature distribution and moisture effects all have to be solved. In addition, larger parts need longer process times. Therefore, reduction of process times and an increase in productivity are necessary in order to enable economic production.
Some of these problems can be solved by using more than one printer head for production, by using new materials and inventing new nozzle systems as distinct solutions for big printers. Nevertheless, to solve all these problems, the development of special machines for large parts is necessary: not component-wise but as a whole system. Large parts could then be successfully produced in several industries, using large, inexpensive FLMmachines.
}},
  author       = {{Villmer, Franz-Josef and Witte, Lars}},
  booktitle    = {{Production Engineering and Management}},
  editor       = {{Padoano, Elio and Villmer, Franz-Josef}},
  isbn         = {{978-3-941645-11-0}},
  keywords     = {{3D printing, FLM, build envelope, large-scale, thermoplastic polymers}},
  location     = {{Trieste, Italy}},
  number       = {{1}},
  pages        = {{111--122}},
  title        = {{{Large Scale 3D-Printers: The Challenge of Outgrowing Do-It-Yourself}}},
  year         = {{2015}},
}