The Magellan Infrared Multiobject Spectrograph Project-2022 Update

The Magellan Infrared Multi-object Spectrograph (MIRMOS) is a near-infrared (NIR) spectrograph with both multi-object (MOS) and integral field unit (IFU) capabilities designed for the Magellan 6.5-meter telescopes. MIRMOS's design is optimized for both faint-object spectroscopy, and with the insertion of a diffuser, for ultra-high-signal-to-noise transmission spectroscopy of exoplanet atmospheres. To maximize MIRMOS's scientific returns, it has an instantaneous wavelength range from 0.89-2.4 mu m with a spectral resolution > 3, 400 in the Y, J, H, and K bands. The front end switches between a mechanical slit mask robot capable of deploying 92 slits over a 13' x 3' field, and an image slicer IFU with a wide field of 26'' x 20''. In this proceeding, we will describe the current state of the instrument, with a focus on its optical design.