Integration of Bragg gratings in aerosol-jetted polymer optical waveguides for strain monitoring capabilities

We demonstrate and discuss the integration of Bragg grat-ings in aerosol-jetted polymer optical waveguides, produced in the optical assembly and connection technology for component-integrated bus systems (OPTAVER) process. By using a femtosecond laser and adaptive beam shaping, an elliptical focal voxel generates different types of single pulse modification by nonlinear absorption in the waveguide mate-rial, which are arranged periodically to form Bragg gratings. Integration of a single grating structure or, alternatively, an array of Bragg grating structures in the multimode wave -guide yields a pronounced reflection signal with typical multimodal properties, i.e., a number of reflection peaks with non-Gaussian shapes. However, the main wavelength of reflection, located around 1555 nm, is evaluable by means of an appropriate smoothing algorithm. When loaded by mechanical bending, a pronounced Bragg wavelength shift of this reflected peak up to 160 pm is detected. This demon-strates that the additively manufactured waveguides can be used not only for signal transmission but also as a sensor.(c) 2023 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement