Optical fibers with different geometries and spectral operation from UV to MIR can be processed to create radial-firing fibers, fused couplers, lensed fibers, bundles, fiber caps, 3D resonators, bended fibers, connections of fiber-to-chip & fiber-to-GRIN lens, etc. At Fraunhofer IZM, a wide variety of fiber optic components have been developed in order to cover the current demand in areas of Telecom, Datacom, Medicine and High-power Lasing. Thin-film lithium niobate enables compact electro-optic structures that operate at very high bandwidth while maintaining predictable behavior. Inside a fiber optic modulator, electrodes shape the. In high-speed optical communication systems, the coupling between optical modules and PHY chips (Physical Layer Chips) is a critical factor determining system data rate, power consumption, signal integrity, and integration level. As data centers evolve from 100G to 400G, 800G, and even 1. 6T. Photoacoustic imaging has emerged as a promising biomedical imaging technique that enables visualization of the optical absorption characteristics of biological tissues in vivo. Highly efficient coupling can directly improve communication quality, and using automatic alignment can significantly reduce the coupling-alignment difficulty. This chapter presents the design of a closed-loop.