ARRANGEMENT AND METHOD AT AN OPTICAL FIBRE

摘要

The present invention relates to an arrangement and a method for selectively switching wavelength channels to and from an optical fibre (1). The arrangement according to the invention comprises at least two fibre couplers (2, 3) and one or more fibre gratings (4) arranged between these. The first fibre coupler (2) is adapted to take off a component of the signal and to switch another component of the signal to a fibre grating. The said grating is adapted to function as a band reflex filter and to prevent selected wavelengts from continuing on the fibre (1) and to reflect these back in the fibre (1). Other wavelengths are allowed to pass further in the arrangement. The second fibre coupler (3) is arranged in a position on the other side of the fibre grating (4) along the optical fibre (1). The said fibre coupler (3) is adapted for introduction of the wavelength removed in the first fibre coupler (2) or for introduction of any other wavelength which is not already present on the fibre.