38.5 km error free transmission at 10 Gbit/s instandard fibre using a low chirp,spectrally filtered, directly modulated 1.55 µm DFB laser

1.55 µm DFB lasers with extremely high bandwidth and low wavelength chirp for local distribution at 10 Gbit/s are described. Time resolved chirp measurements direct from the laser, and after a transient chirp reducing filter, show very small wavelength variations, allowing error free transmission over 18.4 km (without filter) and 38.5 km (with filter) in standard singlemode fibre without the use of dispersion compensation.