We report on the creation of Fiber Bragg Gratings (FBGs) based sensors in large mode area (LMA) fibers. By using a quintupled Nd:YVO4 laser at 213 nm wavelength, FBGs are produced in conventional double clad fibers with core diameters of up to 50 µm. Bragg wavelength shifts depending on applied tensile strain as well as temperature changes are recorded and operating ranges of strain sensors identified. The ease of coupling with light sources into LMA fibers as well as their comparatively elevated robustness makes them promising sensor solutions for harsh environments.
A new transversal pumping scheme of fiber lasers based on the optimized manufacturing of an array of large scale ridge waveguides in fused silica is presented. Moreover their application as directional couplers interacting with a double clad optical active fiber for laser application is discussed. Conventional broad area emitters without slow axis collimation (SAC) can be used to couple light (wavelength λp = 976 nm) into the waveguide array.