ALTAIR (ALTtitude congugate Adaptive optics for the InfraRed) is the facility natural/laser guide star adaptive optics system of the Gemini North telescope. It can feed a corrected beam to Gemini instruments NIRI and NIFS. Deploying ALTAIR is "transparent" for the science instrument, as it reproduces the telescope focal ratio (f/16), pupil size and pupil position.
ALTAIR uses a 177 actuator deformable mirror (DM) and a separate tip-tilt mirror (TTM) to correct atmospheric turbulence. It is equipped with a Shack-Hartmann wave-front sensor (WFS) that uses the visible light to measure the turbulent incident wavefront.