Introduction

GSAOI is designed to be used with GeMS at Gemini South. GSAOI is located at the f/32 output focus of Canopus and can deliver near diffraction limited images in the wavelength interval of 0.9 - 2.5 μm over a 85" x 85" field-of-view, with a scale of 0.02" per pixel. There are four gaps between the arrays of ~2.4mm, corresponding to ~2.5" on sky. It is equipped with a set of broad- and narrow-band filters, a pupil imager to set the instrument alignment and a defocus lenses to null non-common path wavefront error between Canopus and GSAOI. The GSAOI detector is composed of four Rockwell HAWAII-2RG arrays that form a 4080 x 4080 pixel focal plane. The properties of GSAOI near-infrared camera are summarized in the following sections.