Spectral characteristics of semiconductor laser diodes coupled to optical fibres

Abstract

The spectral properties of the light emerging from a single mode fibre coupled to a single mode diode laser has been measured as a function of the fibre length. Reflections from the rear face of the fibre are shown to produce line broadening and satellite modes. For fibres in excess of ~150 m, back-scattering along the fibre core appears to be sufficient to generate satellite modes.