Patent ID: 7672546

Claim:
An optical transport network comprising: a transmitter module comprising; a first integrated circuit chip having a first plurality of sources and a first optical multiplexer, each of the first plurality of sources providing a corresponding one of a first plurality of optical outputs having a respective one of a first plurality of wavelengths, each of the first plurality of wavelengths separated from adjacent ones of the first plurality of wavelengths by a first spectral spacing, the first optical multiplexer configured to receive the first plurality of optical outputs and combine the first plurality of optical outputs into a first output signal provided at an output of the first integrated circuit chip; a second integrated circuit chip having a second plurality of sources and a second optical multiplexer, each of the second plurality of sources providing a corresponding one of a second plurality of optical outputs having a respective one of a second plurality of wavelengths, each of the second plurality of wavelengths separated from adjacent ones of the second plurality of wavelengths by a second spectral spacing, the second optical multiplexer configured to receive the second plurality of optical outputs and combine the second plurality of optical outputs into a second output signal provided at an output of the second integrated circuit chip; and a third optical multiplexer configured to receive the first and second output signals and combine the first and second output signals into a third output signal, the first and second plurality of wavelengths of the third output signal forming a third plurality of wavelengths, each of the third plurality of wavelengths separated from adjacent ones of the third plurality of wavelengths by a third spectral spacing such that the third spectral spacing is less than the first spectral spacing and the third spectral spacing is less than the second spectral spacing.