Tunable laser source with an integrated wavelength monitor and method of operating same

A method of operating an integrated tunable laser comprising:

• sampling light from said laser fabricated on a single integrated semiconductor chip;
• producing two optical signals within the integrated semiconductor chip from light sampled from said laser, which two optical signals are wavelength dependent and distinguished from each other by a different dependence on wavelength;
• detecting said two optical signals within the integrated semiconductor chip to generate two corresponding electrical detection signals;
• generating a wavelength dependent control signal from said two corresponding electrical detection signals;
• and
• feeding back said control signal to said tunable laser to control wavelength of light generated by said laser.

A method of operating an integrated tunable laser comprising:

• sampling light from said laser fabricated on a single integrated semiconductor chip;
• generating two signals within the integrated semiconductor chip from said light sampled from said laser, which two signals are wavelength dependent and distinguished from each other by a different dependence on wavelength;
• generating within the integrated semiconductor chip two detected signals corresponding to said two signals;
• combining said two detected signals within the integrated semiconductor chip to produce a wavelength dependent control signal;
• and
• tuning said laser by feeding back within the integrated semiconductor chip said wavelength dependent control signal to said tunable laser.