Resolution enhanced optical spectrometer having a fixed number of photodetector elements

A waveguide optical monitor comprising:

• an optical input port;
• a plurality of dispersive element input ports;
• an optical switch in optical communication with the optical input port and for switching light received at the optical input port to one of the plurality of dispersive element input ports;
• a plurality of photodetectors for sensing an intensity of light incident thereon;
• a dispersive element for receiving light from any one of the dispersive element input ports and for dispersing the light toward the plurality of photodetectors in dependence upon a position of said dispersive element input port and a wavelength of the light such that light directed from a first of the plurality of dispersive element input ports toward the plurality of photodetectors has associated first centre wavelengths and light directed from the second of the plurality of dispersive element input ports toward the plurality of photodetectors has associated second centre wavelengths, the second centre wavelengths forming a set different from a set formed by the first centre wavelengths.

A method of monitoring a wavelength division multiplexed optical signal comprising the steps of:

• providing an optical signal to a switch;
• selecting a switch mode for selectably providing the optical signal via one of a plurality of input ports to a dispersive element;
• dispersing the optical signal in dependence upon the location of the selected input port and in dependence upon a wavelength of the optical signal and directing the dispersed optical signal toward a plurality of monitoring elements,
• wherein selecting different switching modes results in light within a different wavelength range being incident upon a same detector.

A thermally modulated optical channel monitor comprising:

• a waveguide made of a material having a temperature dependent refractive index, the waveguide comprising a dispersive element for dispersing received light in dependence upon wavelength;
• a temperature adjust element for varying the temperature of the waveguide;
• and,
• a sensor for sensing an intensity of light incident thereon forming a portion of the received light, the portion varying in dependence upon the waveguide temperature, the sensor for sensing an intensity of light at different waveguide temperatures, the different waveguide temperatures providing for sensing of a signal at different wavelengths.

A thermally modulated optical channel monitor for monitoring an optical signal comprising:

• a waveguide made of a material having a temperature dependent refractive index, the waveguide comprising a dispersive element for separating the optical signal into a plurality of separated optical signals based upon wavelength;
• a temperature adjust element for varying the temperature of the waveguide;
• at least a sensor for sensing an intensity of light of at least a separated optical signal at different waveguide temperatures, the intensity of light being dependent upon the waveguide temperature, the different waveguide temperatures providing for sensing of the at least a separated optical signal at different wavelengths;
• and,
• a monitor sensor for sensing a parameter indicating the waveguide temperature at each instance an intensity of light was sensed.

A method for monitoring an optical signal comprising the steps of:

• providing a waveguide made of a material having a temperature dependent refractive index, the waveguide comprising a dispersive element for dispersing light in dependence upon wavelength;
• providing a temperature adjust element for varying the temperature of the waveguide;
• providing a sensor for sensing an intensity of light incident thereon;
• and,
• sensing an intensity of light at different waveguide temperatures, the intensity of light being dependent upon the waveguide temperature, the different waveguide temperatures providing for sensing of a signal at different wavelengths.

A method for monitoring an optical signal comprising the steps of:

• providing a waveguide made of a material having a temperature dependent refractive index, the waveguide comprising a dispersive element for separating the optical signal into a plurality of separated optical signals based upon wavelength;
• providing a temperature adjust element for varying the temperature of the waveguide;
• providing the optical signal to the waveguide;
• sensing an intensity of light of at least a separated optical signal at different waveguide temperatures, the intensity of light being dependent upon the waveguide temperature, the different waveguide temperatures providing for sensing of the at least a separated optical signal at different wavelengths;
• sensing a parameter indicating the waveguide temperature at each instance an intensity of light was sensed;
• and,
• sampling the intensities of light of the at least a separated optical signal and the corresponding parameters indicating the waveguide temperature.