Printing and preparation of integrated optical waveguides for optronic sensor networks

Printing processes are employed to create three-dimensional transparent structures which serve as multimode optical waveguides in intelligent systems. The additive manufacturing techniques deliver integrated elements for optical signal transmission in optical communications and novel optronic sensor systems. These networks of sources, sensors and detectors consist of polymers and rely entirely on the conversion of light for space resolved measurements. Measured quantities are temperature, strain and chemical concentration in application scenarios such as structural health monitoring and the life sciences.Results show the suitability of flexographic and inkjet printing to generate parabolic shaped waveguides with a minimum lateral dimension of 50 μm and maximum height of 110 μm. We describe the geometrical properties of printed waveguides as basis for further integration of functional elements.End facets of waveguides serve as interfaces to adjacent functional elements. We compare the capabilities of several processes for end facet preparation of printed polymer waveguides. Stress-induced cleaving is presented as a highly effective procedure with a root mean square surface roughness smaller than 60 nm.