Ring laser gyroscope

Abstract

Abstract The invention is concerned with angular rate sensors, and particularly with ring laser gyroscopes which includes means for compensating for the effects of temperature gradients and residual lock-in. A ring laser gyroscope is provided which has a triangular block configuration, and which incorporates a triangular-shaped laser resonant cavity defined by three corner mirrors, including an output mirror. The ring laser gyroscope of the invention includes an optical wedge and a prism attached to its output mirror which permit the center of support of the gyroscope to be located in the plane of symmetry of the block. The gyroscope is mechanically vibrated about its center of gravity to prevent lock-in effects at low angular input rates. The construction of the gyroscope reduces temperature gradients across the plane of symmetry of the instrument, which temperature gradients produce spurious output signals in the absence of an input angular rate. The optical wedge and prism, together with an external corner cube retro-reflector, form an interferometer which provides compensation for the output signal of the gyroscope, enabling the gyroscope to produce an output free from the influence of the mechanical vibrations over a substantial angle, and which permits large angle low frequency mechanical vibrations to be introduced to prevent lock-in effects, which large angle low frequency vibrations have no tendency to cause residual lock-in effects to occur which produce non-linearities in the scale factor of the laser.

Inventors

• 👤 Bo H. G. Ljung
• 👤 George R. Gamertsfelder

Bibliographic Details