The OptiK‑Net consortium set out to combine printed polymer waveguides with rigid‑flex printed circuit boards to create a new, cost‑effective data‑transmission technology. The goal was to enable high‑throughput, fully automated assembly of the waveguides onto transmitter and receiver units, thereby opening the way to mass production of short‑range optical networks. The German Federal Ministry of Education and Research (BMBF) funded the project under grant number 13N15049, with a duration from 1 October 2019 to 31 March 2023. The consortium comprised eight partners: Hotoprint Elektronik GmbH & Co. KG (project lead, PCB and electronics manufacturing), Leibniz University Hannover (research on flexographic production and characterization), ContiTech Elastomer‑Beschichtungen GmbH (rubber‑tissue platform technologies for flex‑printing), Jänecke + Schneemann Druckfarben GmbH (printing inks), Janoschka Deutschland GmbH (deep‑etching for printing cylinders), ficonTEC Service GmbH (special machine building for optical assembly and bonding), Siemens AG (application of galvanically isolated circuits), Gallus Ferd. Ruesch AG (machine building for printing presses), and Continental Automotive GmbH (application of optical data transmission in e‑mobility). ficonTEC was primarily responsible for work package 4, which covered the design and implementation of the handling system, bonding process, optical alignment, and the laboratory assembly of demonstrators. The company also contributed to the overall concept (work package 1) and to the construction of the demonstrators (work package 5).

Technically, ficonTEC developed a novel gripping and alignment tool that prevents twisting and bending of the flexible waveguides during pick‑up. The tool allows the waveguide to be measured by a top‑view camera while maintaining its straightness. An optimized adhesive process was introduced that can be cured with ultraviolet light in under ten seconds, enabling rapid bonding of the waveguide to the PCB with minimal gap. The adhesive also provides strain relief for the waveguide. Optical alignment studies identified a process window for passive coupling of laser diodes to photodiodes, showing that a horizontal and vertical alignment tolerance of ±10 µm is sufficient for reliable operation. The overall assembly sequence was defined as: (1) mounting of the laser diode and photodiode onto the PCB, (2) electrical connection of the two components, and (3) placement of the flexible waveguide between the transmitter and receiver units. Five demonstrators were built and validated in a laboratory environment, demonstrating the feasibility of the automated process and confirming the performance of the optical coupling and bonding steps.

The project achieved its core objective of establishing a fully automated, mass‑production‑ready process for mounting printed polymer waveguides onto rigid‑flex PCBs. The developed handling system, bonding technique, and optical alignment concept collectively enable high‑throughput assembly while preserving the integrity of the flexible waveguides. The demonstrators proved that the process can be scaled and integrated into existing manufacturing lines, providing a foundation for future commercial deployment of short‑range optical networks. No significant changes to the original objectives were required, and no additional research and development results were identified that would alter the scope of the work. The collaboration among the eight partners, each contributing specialized expertise, ensured that the technical challenges were addressed comprehensively within the allocated timeframe and budget.