Innovative optical techniques used in the Raman instrument for ExoMars

The optical part of the Raman Laser Spectrometer (RLS) instrument for ExoMars consists of an excitation laser, an optical harness, an optical head and a spectrometre. The optical harness delivers the green radiation generated by the laser to the optical head which, in turn, focuses the laser radiation on the sample of interest and collects the Raman emission from the sample. The optical head then separates excitation light and Raman emission by a filter setup and sends the isolated Raman signal to a reception fiber, which delivers it to the spectrometer of the instrument. This paper concentrates on the innovative technologies applied for the excitation path of the instrument, the laser, the optical harness with its new compact fiber optic connectors and the Raman optical head; and describes their design, the design driving requirements and the status these units have reached by now. The spectrometer of the system with its transmission grating design will be presented separately.