  Over the past two decades, photonics have been developed as technological
solutions for astronomical instrumentation for, e.g., near-infrared
spectroscopy and long baseline interferometry. With increasing instrument
capabilities, large quantities of high precision optical components are
required to guide, manipulate, and analyze the light from astronomical sources.
Photonic integrated circuits (PICs) and fiber-based devices offer enormous
potential for astronomical instrumentation, as they can reduce the amount of
bulky free-space optics and pave the way for innovative solutions.
Astrophotonic devices are particularly interesting for interferometry due to
their compact design on the centimeter scale, even for a large number of
telescope inputs. Already, astrophotonic components are integrated in high-end
instruments at the VLTI and at the CHARA Array. Photonic beam combiners at
wavelengths from visible to mid-infrared have been fabricated using
lithographic techniques or ultrafast-laser inscription, with several components
tested on-sky. This paper will provide a glimpse into the growing field of
astrophotonics, its current status and potential for new technologies.
