Recording of efficient high-order Bragg reflectorsinoptical fibres by mask image projection and singlepulse exposure with an excimer laser

A technique using high resolution mask projection for creating efficient Bragg grating reflectors in optical fibres by single excimer laser pulse exposure is described. Using a deep UV projection system with a large image field size and micrometre resolution, gratings with periods between 1 and 6 µm have been recorded in Ge-doped fused silica fibres that produce high order Bragg reflections in the wavelength range 1.43–1.65 µm.