Abstract:
The coming decade in astronomy focuses on large widefield imaging and spectroscopic
surveys. No widefield imaging facility extends to the UV region, which represents an
important window into a wide variety of astrophysical problems. Also, spectroscopy would
be essential to understand the physical and chemical properties of several stars, star forming
regions and galaxies.
INSIST (the INdian Spectroscopic and Imaging Space Telescope) is a proposed future space UV
mission to be able to observe in the UV (150nm-300nm), u (300nm-400nm) and g (400nm550nm) bands. Multi Object Spectrograph (MOS) is one of the key instruments proposed for
INSIST to work in the UV band and efficiently obtain spectroscopic data for a large number of
objects at a much shorter timescale. MOS is designed with a programmable reflective slit
through a Digital Micromirror Device (DMD), which is an innovative opto-electro-mechanical
component consisting of a 2-dimensional array of tiny mirrorlets that can be flipped to two
orientations by command.
DMD is to be used in a telescope in the UV region for MOS application for the first time in
space. Hence, it is necessary to understand and study the functionality of DMD and its
suitability to space telescopes. As part of this project, a spectrograph was designed with the
DMD and set up on an optical bench in the laboratory. The performance and various
parameters of the DMD were tested and the results are reported. Models were made for
fabrication of an assembly to be tested at the J. C. Bhattacharya Telescope (JCBT) at Vainu Bappu Observatory in optical region.
