Abstract

Fibre gratings with broad reflection bandwidths have many applications in fibre optic systems including dispersion compensation elements¹ and external cavity reflectors for mode-locked lasers.² A large reflection bandwidth may be achieved from a uniform period grating with a very strong coupling coefficient? However, we must also distinguish between those applications which demand only the broad bandwidth, and those which utilise the spatial dependence of the peak reflected wavelength as occurs in a grating with chirped period: applications specified by Refs. 1 and 2, for example, largely fall into this category. Despite the undoubted interest in chirped fibre gratings, very little has been reported on their fabrication and characterisation.

© 1994 IEEE