The Smart Slit Assembly (SSA) combines the slit homogenizer based on an array of rectangular waveguides and the smart slit based on MEMS shutters. The SSA is placed in the focal plane of the front optics (e.g. telescope) where the classical slit would be placed.
The SSA is aiming to diverse applications in Astronomy, namely Multi-Object Spectroscopy (e.g., NIRSpec on JWST) as well as in Earth/Planetary Observation (e.g., Atmospheric Science).
The performance of spectrometers will be significantly improved due to the following advantages of the SSA: scene/object selection; scene/object intensity equalization; inflight monitoring and calibration functions; pixel level scrambling of intensity, polarization and phase; mechanical decoupling of optical instrument parts; increased spectral stability / reduced noise on spectral detection and reduced polarization sensitivity (polarization scrambler).
The SSA comprises two distinct waveguides (rectangular fiber) as the transmitting channels separated by a gap which provides the space for placing the shutter blade to block the light path (MEMS device). Input/output ports (IO port) and MEMS ports act as holders for optical fibers. The main features of the proposed concept are analog gray scale level, high filling factor, array scalability, 40 channels and electrostatic MEMS actuation.
The project includes design of all components of the SSA – IO ports, MEMS ports and MEMS device chip. COMSOL software is used for simulation and optimization. At the end of this project we will deliver the complete and working SSA with the control unit.
Funding and Partners
The project duration is 18 months, starting in March 2019. The project is funded by the European Space Agency. All fabrication and assembling steps, as well as characterization, are performed at EPFL with the help of Center of MicroNanoTechnology (CMi) facilities. Project partners are OHB System AG and Micos Engineering GmbH.
For more information refer to the SSA page on the ESA website.