GRIM: a near-infrared grism spectrometer and imager

This paper describes the near-infrared grism spectrometer and imager (GRIM) designed for use on the Astrophysical Research Consortium telescope. The GRIM system incorporates a wide range of imaging, spectroscopic, and polarimetric capabilities. Attention is given to the mechanical and optical layout of GRIM, the details of the optical design, and the basic components of the remote observing system.