APPARATUS FOR ELIMINATING ACTIVATION NOISE IN A LASER GYROMETER, AND LASER GYROMETER EMPLOYING THIS APPARATUS

摘要

1. An apparatus for eliminating activation noise in a laser gyrometer, comprising : - an optical unit mounted for rotation on a support (3) and provided with at least one optical perimeter forming a closed loop, inside which two laser radiation beams in opposite directions are produced, - means adapted to effect a mixing of these two radiations so as to obtain a system of parallel interference fringes, - a device (15, 16) adapted to supply an impulse signal the impulses of which are representative of an increment of the angle of rotation of the optical unit (1) with respect to a system of reference coordinates based on measurement of the frequency of movement of the interference fringes, - means for mechanical activation adapted to put the optical unit (1) into oscillation with respect to its support (3) and - means for subtracting from the signal representative of the rotation of the optical unit (1) with respect to the system of reference coordinates, a signal representative of the oscillation of the optical unit (1) with respect to its support (3), characterized in that the signal representative of the oscillations of the optical unit (1) with respect to its support (3) is obtained by means of an electromagnetic sensor (8) comprising at least two parts movable with respect to each other and respectively secured to said optical unit (1) and to said support (3) said electromagnetic sensor (8) being arranged so as to supply an analog signal representative of the relative angular speed of the optical unit (1) with respect to its support (3).