]>Properties of Specialist Fibres and Bragg Gratings for Optical Fiber Sensors : Figure 1
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Figure 1: Examples of common structured optical fibres into which gratings have been written: (a) low loss ( < 4 dB/km) 4-ring all-silica photonic crystal optical fibre; (b) 12-ring photonic crystal fibre with triangular core and photosensitive, high NA step-index germanosilicate centre; and (c) a simple Fresnel fibre.