Narrow-band Bragg filters for the 1.5-μm spectral region based on polished-side single-mode silica fibres

Narrow-band reflecting filters for the telecommunication 1.5-μm wavelength region are fabricated. They consist of a single-mode silica fibre with a polished side and a periodic relief Bragg grating located in the region of the fibre-mode propagation. The filters have the reflectivity R > 98 % and an almost rectangular reflection band with a width of 0.58 – 0.78 nm. They can be used as elements of optical multiplexers/demultiplexers for combining and separating signals in high-speed multichannel fibreoptic communication lines.