All fiber gyro

An all fiber gyroscope has been developed having the following features: small size, rugged construction, and long term stability. The main components of the gyro include: a taper coupler, a fiberoptic Lyot-depolarizer, and a phase modulator driven at a frequency tau is equal to about 120 kHz (where tau denotes the transit time of the signal through the fiber coil). The achieved drift and noise equivalent rotation rate of the gyroscope are estimated near 0.62 degrees and 1.83 degrees per hour, repectively, for an integration time of 30 seconds. A schematic diagram of the device is provided.