Patent ID: 7103239

Claim:
An optical transmitter comprising: a monolithic transmitter photonic integrated circuit (TxPIC) chip comprising an array of modulated sources formed on the PIC chip and having different operating wavelengths according to a standardized wavelength grid and providing signal outputs of different wavelengths; a wavelength selective combiner formed on the PIC chip having a wavelength grid passband response approximating the wavelength grid of the standardized wavelength grid; the signal outputs of the modulated sources optically coupled to inputs of the wavelength selective combiner and provided as a combined signal output from the combiner; a first wavelength tuning element coupled to each of the modulated sources; a second wavelength tuning element coupled to the wavelength selective combiner; a wavelength monitoring unit coupled to the wavelength selective combiner to sample the combined signal output; a wavelength control system coupled to the first and second wavelength tuning elements and to said wavelength monitoring unit to receive the sampled combined signal output; the wavelength control system for adjusting the respective wavelengths of operation of the modulated sources to approximate or to be chirped to the standardized wavelength grid and for adjusting the optical combiner wavelength grid passband response to approximate the standardized wavelength grid.