Bend Insensitive Optical Fiber
Bend insensitivity can be considered in terms of both the mechanical and optical performance of a fiber.
In the case of a mechanically bend insensitive fiber, a reduced cladding such as 80µm or 50µm offers an improved coil lifetime *(see Reduced Clad 80µm Fiber entry)*.
In terms of optically bend insensitive fiber, this means that a fiber has been designed to mitigate the optical losses that are associated with tight bend radii. This can be achieved by a few different approaches:
1. Increased germanium content in the core (as indicated by an increased numerical aperture (NA)).
2. Increased core diameter (as indicated by an increased second order cut-off wavelength).
3. Fluorine doped inner cladding (either as doping immediately surrounding the core to increase NA, or as a trench at small distance radially out from the core edge).
Both of these approaches ensure that the light is more tightly confined within the core and thereby reduce Bend Induced Losses (BIL).
For more information, please request our technical note