Multicore Fibers for 3D Measurements
In the standard configuration, multicore fibers have seven cores in a 125 µm cladding. Each of these fiber cores can be used in signal transmission to transmit different signals simultaneously. This can significantly reduce the number of fibers. With the space division multiplexing (SDM) method, several signal lines can be switched in data centers and switching stations at one connection slot. This allows higher bandwidths to be achieved with a smaller number of cables and connections. Multicore fibers for data transmission are optimized for the 1550 nm telecom wavelength.
Multicore Fibers with Fiber Bragg Gratings
Fiber Bragg gratings are reflection gratings that filter out a certain wavelength. This wavelength changes when the fiber is bent, drawn, or heated. This makes extremely accurate measurements possible.
Multicore Spun Fibers with FBGs
These multicore fibers are not only equipped with FBGs but are also twisted up within themselves. If four cores are used in these fibers, a distinction can be made between rotations to the left and right. In versions with five cores, the middle core is added as a reference channel. This allows the temperature and load effects acting on the fiber to be referenced out.
Fibers as 3D Sensors
FBG-spun multicore fibers are particularly well suited for 3D sensors. In bridges and other structures, they serve as motion sensors and are used in earthquake warning systems. In medicine, FBGs can be used to detect the exact position of fibers in the body during endoscopy.