Method and system for linearization of MOEMS tunable filter scan

摘要

One problem that arises in the context of controlling tunable filters, and more specifically, Fabry-Perot tunable filters concerns the control algorithms for these MOEMS devices. An optical filter system comprises a tunable optical filter that scans a pass band across a signal band to generate a filtered signal. A filter tuning voltage generator generates a tuning voltage to the optical tunable filter. A photodetector generates an electrical signal in response to the filtered signal. Finally, a controller, that is responsive to the photodetector, triggers the filter tuning voltage generator. To increase the ease at which the results of a scan of the signal band of a WDM signal can be analyzed and improve spectral resolution, the change in the pass band of the tunable filter as a function of time is linearized in frequency or wavelength. This is achieved through the use of essentially an arbitrary waveform generator as the filter tuning voltage generator. The generator is programmed with an inverse of the filter's tuning characteristic.