Suitable for sensors used in Raman spectroscopy systems to detect chemical, biological, radiological, nuclear, or explosive weapons, Model 275D works as tunable filter, adjustable Raleigh edge-rejection, and bandpass. Double-monochromator can work to wavelengths as short as 190 nm and includes wavelength tuning for signal optimization. Diffraction gratings with aberration correction and optimal efficiency from 190 nm ultraviolet to infrared are available.