Spectrolight (Irvine, CA; www.spectrolightinc.com) – Flexible Wavelength Selector. The Flexible Wavelength Selector (FWS) combines the wavelength tunability and adjustable bandwidth of a traditional monochromator with the circular uniform aperture of a bandpass filter. FWS products employ Spectrolight’s TwinFilm™ Technology—a next-generation approach to wavelength filtering and scanning.