Ring laser gyroscope

About: Ring laser gyroscope is a research topic. Over the lifetime, 2070 publications have been published within this topic receiving 18609 citations. The topic is also known as: Sagnac interferometer.

Ring laser gyro

Abstract: PURPOSE:To obtain a ring laser gyro, which has no degradation in reliability due to the problem of coupling for taking out an output and is suitable for mass production, by forming specific ring lasers, an output waveguide, a light detector, and a nonreflecting terminal in the same substrate. CONSTITUTION:Y branches 11a and 12a having directivity are provided in ring lasers 11 and 12 so that they are oscillated only in the reverse direction each other. They are not oscillated to the other directions since propagation loss is large. The ring laser 11 is oscillated only in the clockwise direction, and the ring laser 12 is oscillated only in the counterclockwise direction. An output waveguide 13, which forms a directional coupler that is coupled to both ring lasers 11 and 12, is provided between the two ring lasers 11 and 12. The parts of the outputs of the ring lasers 11 and 12 are taken out and synthesized, and the result is guided to a light detector 15. At the other end of the output waveguide 13, a nonreflecting terminal 14, which absorbs the reflection from the light detector 15 and natural emitted light from the ring lasers 11 and 12, is provided.

Small jitter frequency stabilization method of four-frequency laser gyro

Abstract: When a four-frequency laser gyro adopts light intensity difference for frequency stabilization, accuracy thereof is easily influenced by parameter variation in light combination, photoelectric conversion and amplification processes. The invention discloses a novel frequency stabilization mode, small jitter modulation is carried out on path length of the four-frequency laser gyro, and then frequency stabilization is carried out according to the modulation condition of four-frequency laser gyro intracavity travelling wave mode amplitude, so that the four-frequency laser gyro operates under the condition that homonymous travelling wave mode beat-wave amplitude is maximum. The invention can solve problems which are caused when light intensity difference is adopted for frequency stabilization, and performance of four-frequency laser gyro is improved while the four-frequency laser gyro operates in unique uninterrupted state.

System, apparatus, and method for resonator and coriolis axis control in vibratory gyroscopes

Abstract: A gyroscope control circuit for a vibratory gyroscope system includes an open-loop RSP control circuit and a closed-loop CSP control circuit. The gyroscope control circuit optionally may include a Q compensation circuit to compensate for variations in gyroscope sensitivity due to variations in resonator signal path Q. The resonator signal path and the Coriolis signal path may have transduction factors that are proportional to each other such that sensitivity of the gyroscope varies directly with resonator signal path quality factor (Q).

Open-loop fiber-optic gyroscope using intensity-modulated source and phase modulation.

Abstract: A simple open-loop approach to a standard fiber-optic gyroscope that uses an intensity-modulated source is described. Direct readout of the Sagnac effect in an open-loop form is obtained by applying a sinusoidal modulation to the source and the phase modulator at the proper frequency, with the modulation depth of the source adjusted appropriately. Experimental results show good linearity over a wide dynamic range.

Ring laser gyro having ring resonator semiconductor lasers and driving method thereof

Abstract: A ring laser gyro includes a tapered portion in a part of an optical waveguide, a plurality of ring resonator semiconductor lasers optically independent of each other on a common plane, and a plurality of electric terminals for detecting a change in the impedances of said ring resonator semiconductor lasers. The tapered portion includes a first portion where a width of the optical waveguide is gradually widened along a direction of propagating a laser beam clockwise and a second portion where the width of the optical waveguide is gradually narrowed along the direction, and further comprising a first ring resonator semiconductor layer in which said first portion is longer than the second portion, and a second ring resonator semiconductor layer in which said second portion is longer than the first portion.