James Webb Space Telescope microshutter arrays and beyond

Microshutter array (MSA) subsystems were developed at NASA Goddard Space Flight Center as multiobject selectors for the Near-Infrared Spectrograph (NIRSpec) instrument on the James Webb Space Telescope (JWST). The subsystem will enable NIRSpec to simultaneously obtain spectra from > 100 targets, which, in turn, increases instrument efficiency 100-fold. This system represents one of the three major innovations on the JWST that is scheduled to be launched in 2018 as the successor to the Hubble Space Telescope. Featuring torsion hinges, light shields, magnetic actuation, and electrostatic latching and addressing, microshutters are designed for the selective transmission of light with high efficiency and contrast. Complete MSA assemblies consisting of 365 × 171 microshutters were successfully fabricated and tested, and passed a series of critical reviews for programmable 2-D addressing, life tests, and optical contrast tests. At the final stage of the JWST MSA fabrication, we began to develop the next generation microshutter arrays (NGMSA) for future telescopes. These telescopes will require a much larger field of view than JWSTs. We discussed strategies for fabrication of a proof-of-concept NGMSA that will be modular in design and electrostatically actuated. The details of NGMSA development will be discussed in a follow-up paper.