Excitation of Whispering Gallery Modes in Fibres by Fibres

Fig 1. Tro*9mmo= SPecrmm of the 'em, that away from the resonance. ~~~~~~~i~~ resonances are separated by about 30 nm, a free toper at e WGM ILIOM~C~ of the migii raper, spectral range consistent with the target's diameter. Reduction of the sensor's diameter or cniargemenl of the target's increases the width and depth of the resonances. These spectral characteristics cwld lead to all-fibE narrowband filters(2), prhaps for WDM. However, our fint application was to mmure the non-uniformity of tapered fibres to high accuracy: $2