Patent ID: 7512295

Claim:
A photonic integrated circuit chip comprising: a substrate; a plurality of distributed feedback (DFB) laser sources provided on the substrate, each of the plurality of DFB laser sources directly modulated to provide a corresponding one of a first plurality of optical outputs at a respective one of a plurality of wavelengths, each of the plurality of DFB laser sources having a first end and a second end that each supply a corresponding one of the first plurality of optical outputs; a plurality of variable optical attenuators (VOAs) provided on the substrate, each of the plurality of VOAs coupled to the first end of a corresponding one of the plurality of DFB laser sources to receive a corresponding one of the first plurality of optical outputs, each of the plurality of VOAs providing a corresponding one of a second plurality of optical outputs; and a wavelength selective combiner provided on the substrate having a plurality of inputs and an output, each of the plurality of inputs of the wavelength selective combiner coupled to a respective one of the plurality of VOAs to receive a corresponding one of the second plurality of optical outputs, such that the second plurality of optical outputs are multiplexed by the wavelength selection combiner and supplied as an WDM signal at the output of the wavelength selective combiner.