Properties of Specialist Fibres and Bragg Gratings for Optical Fiber Sensors
Figure 4
(a)–(f). Numerical simulation of (red) optical localisation in varying hole size within a bandgap Fresnel fibre and (blue) optical localisation within the silica. As the hole size becomes smaller (a and b), a step-like discontinuity arising from the interface boundary is observed [34]. There appears to be enhanced field localisation of the evanescent field in addition to that expected from the far-field phase diffraction of the Fresnel structure.
