Patent attributes
Methods use a tunable notch filter for constructing a spectral map of electromagnetic radiation in a selected spectral band that is incident on a notch filter for a plurality of time periods. Electromagnetic radiation is passed by an electronically tuned notch filter to a detector array for the plurality of selected time periods, and the detector response is determined. For at least a first selected time period the notch filter is tuned to selectively attenuate the passing of one or more selected sub-bands of electromagnetic radiation in the selected spectral band. Information about the selectively attenuated radiation is determined and used along with information about the radiation passed to the detector array for each time period to construct a spectral map. Electronically tunable notch filters may be made with metamaterials such as patterned graphene.