CLOSED-LOOP CONTROL OF TUNABLE OPTICAL WAVELENGTH FILTERS

摘要

A wavelength selective optical device for locking to a selected wavelength in an ITU grid includes a first waveguide, a second waveguide, a heating element and a control unit. The first waveguide includes a tunable filter formed in the first waveguide and the second waveguide includes a reference filter formed in the second waveguide. The heating element is in thermal contact with the tunable filter and the reference filter and the control unit is coupled to the heating element and the reference filter. The control unit varies a temperature of the heating element responsive to an indication signal provided by the reference filter to adjust the selected channel of the tunable filter.