Solid-state multioscillator ring laser gyro using a <100>-cut crystalline gain medium

A multioscillator ring laser gyro for measuring relative angular position or angular velocity along a defined rotation axis, comprising at least an optical ring cavity, a solid-state amplifying medium and a measurement device that are arranged in such a way that a first linearly polarized propagation mode and a second linearly polarized propagation mode, perpendicular to the first mode, are able to propagate in a first direction in the cavity and in such a way that a third linearly polarized propagation mode parallel to the first mode and a fourth linearly polarized propagation mode parallel to the second mode are able to propagate in the opposite direction in the cavity, wherein the amplifying medium is a crystal of cubic symmetry having an entry face and an exit face, the crystal being cut so that said faces are approximately perpendicular to the <100> crystallographic direction, the angles of incidence of the various modes on said faces being approximately perpendicular to said faces.