The Ohio State Infrared Imager/Spectrometer (OSIRIS) is a multi-purpose infrared imager and spectrometer. Following many years of succesful use as a facility instrument on the CTIO 4-m Blanco and 1.5-m telescopes it was moved to SOAR,  installed at one of the f/16.62 Nasmyth Focii.

OSIRIS uses a 1024x1024 HgCdTe array supplied by CTIO to opperate at wavelengths from 0.9 to 2.4 microns. Internal optics allow for two plate scales and a variety of spectroscopic resolutions. Internal mechanisms control the selected filter, focal plane mask, pupil mask alignment, grating tilt, and optical arrangement. All mechanisms are user controlled and can be used to rapidly reconfigure the instrument, which allows for substantial observing flexibility.

Ohio State University web page for OSIRIS [1]