Induced Bragg Gratings in Optical Fibers and Waveguides Using an Ultrafast Infrared Laser and a Phase Mask
Figure 21
The spectra of the probe grating before and after the cladding exposure are denoted by black and grey traces, respectively. Inset photomicrograph shows a type II-IR exposure in SMF-28 fiber in the cladding proximate to the core. Image taken along the exposure beam axis (b) shows a schematic representation of the exposure conditions that produced the high birefringent spectral result.