Production of Bragg gratings in optical fibres by holographic and mask projection methods

A high-resolution, excimer laser-based projection system has been used to write first order Bragg gratings in single-mode optical fibres at 1530 nm using an optical phase-shifting mask. This is, to our knowledge, the first demonstration of the writing of sub-micron period gratings using phase mask projection methods. Biprisms have also been used to write first-order gratings in fibres at 1661 nm with single pulses from an excimer laser at 248 nm