Far-UV multi-object spectroscopy with digital micromirror devices (DMDs)

摘要

Digital micromirror devices (DMDs) can bo used as versatile, rapidly reconfigurable object selectors in space-based multi-object spectrographs (MOS). DMDs are inexpensive, compact, reliable, high-throughput devices, that enable extremely flexible and efficient multi-object spectrographs: several DMD-based MOSs are currently being built for 4 m class ground-based telescopes. Previously, we have shown that DMDs are suitable for deployment and operation in space, in the ncar-UV and optical regimes (200 - 1000 nm). Using aluminum coatings protected with LiF and LiF/AlF3 films, we aim to extend the operational range of DMDs into the 100 - 200 nm FUV regime. Our initial coating runs produced DMDs with reflectivity > 40% in the range of 110 -180 nm. Critically, the DMDs remain operational after the coating process. We will discuss potential for further improvement and introduce several mission concepts based on a FUV/NUV DMD MOS, that can be deployed on CubeSat and ESPA-class missions.