Laser deposition of fused silica coreless fibers to generate functional waveguides

There is an increasing demand for highly integrated optical and optoelectronical devices that provide active laser emission, adaptability and low losses. A well-established production technology for customized structures with high functionality and geometrical flexibility is additive manufacturing (AM). Commercial AM systems for metals and polymers are ubiquitous; whereas glass AM systems only exist in scientific environments. In this paper, the deposition of coreless fused silica fibers with a diameter of 400 µm and a 50 µm thick polymer coating onto a glass substrate with defocused CO2-laser radiation (10.6 µm) is demonstrated and investigated. The guiding efficiency, surface smoothness and internal stress of the deposited fiber are characterized and compared with an untreated fiber. This results in functional, nearly stress-free waveguides for light transmission with high position stability and opens a range of applications for optical system integration.