Abstract: A beam combiner assembly for a ring laser gyroscope is fabricated by positioning two diffraction gratings, mounted onto respective light transmissive substrates, with respect to the output mirror of the gyro block at an offset angle such that an interference fringe pattern is projected onto the photodetector of the ring laser gyroscope. By tilting the diffraction gratings, with respect to the plane of the output mirror, a corrected number of lines per unit length for the diffraction gratings may be effected, thereby providing a beam combiner assembly which is compensated for manufacturing imperfections and other intolerances. Also, the high sensitivity of angular adjustments for the conventional prism beam combiner is overcome.

Abstract: A resilient serpentine shaped tungsten wire is formed to match a short wire section to hold a ring laser gyroscope getter. The getter-holder assembly is positioned within a stepped oblong bore so that the getter is in firm contact with the bore surface at two points. This prevents resonances of the getter or holder that might otherwise destroy the getter while subjected to vibrations.

Abstract: A monolithic ring laser gyroscope is formed by six mirrors mounted to the respective center of each face in a cube. Bores in the cube interconnect each of the mirrors. Three orthogonal planes are defined within the cube, each of which contains a laser cavity. Accordingly, three orthogonal beam paths exist, each responsive to rotational inputs about three orthogonal axes.

Abstract: A ring laser gyroscope has at least two of its mirrors vibrated perpendicular to their reflective surfaces by equal and opposite amounts to maintain the total beam path length constant. The amplitude of vibration causes the beams to be shifted across surfaces of all of the mirrors by a distance that is at least close to a Bessel zero distance so as to reduce the intensity of back scattered radiation at the main wavelength to a value close to zero. For an equilateral triangular ring laser gyroscope, two of the mirrors are vibrated between about 0.66.lambda. and 0.74.lambda., optimally about 0.71.lambda.. For an isosceles triangle having vibrating mirrors at two vertexes having angles of about 51.65.degree., the magnitude of vibration should be about 0.91.lambda..

Abstract: In a ring laser gyroscope having a triangular optical resonator with mirrors at its corners, in order to prevent lock-in, a portion of the light from the beams that passes through the mirrors at the corners is fed back into the clockwise and counter-clockwise beams after being passed through an optical resonator containing a nonreciprocal phase shifter.