Tunable wavelength light filters are important components of spectral imagers, optical communications networks, and sensor networks. Most are based on Fabry-Perot (FP) technology. The classic FP interferometer, or etalon, is a pair of highly polished mirrors that face one another to create a resonant cavity that interferes constructively, dispersing a specific wavelength depending on tune. The Segmented Tunable Filter from Scientific Solutions, Inc., North Chelmsford, Mass., improves the FP technology by filling the resonant cavity with liquid crystal rather than air and etching the optically-transparent conductive layer that carries the electric field in the liquid crystal FP cell. The result is multiple, independently-tunable etalon segments on a single substrate with no moving parts and 100% repeatable and stable wavelength selection. The filter can have a virtually unlimited number of spectral “channels”, each of which can be independently tuned to a separate wavelength with spectral resolutions as narrow as 0.002 nm in the visible spectrum range (400-800 nm). Up to 128 channels are possible, and power consumption is low, 0-10 V. The level of resolution matches or exceeds piezo-based systems that are limited to just one channel.