| abstract |
A series combination of a shortwave pass (SWP) filter (12-S, 14-S) and a longwave pass (LWP) filter (12-L, 14-L) is provided in an arrangement where the filters are separately and independently controlled by voltages applied to the respective filters. The applied voltages modify the response profile of the associated filters, where changes in the voltage applied to the SWP filter (12-S, 14-S) changes its cut-off wavelength λ S and changes in the voltage applied to the LWP filter (12-L, 14-L) changes its cut-on wavelength λ L (the bandwidth of the combined arrangement between the span between λ L and λ S ). The ability to independently tune both the SWP and LWP filters allows for the combined result of their series combination to modify both the center wavelength (CWL) and bandwidth (BW) of the overall filter resulting from their combination. |