| 摘要 |
An improved fiber optic rotation sensing technique and an improved optical fiber gyro are provided which exhibit increased sensitivity to and linearity of rotation measurement by using a special dual-section, counter-wound fiber coil for measuring the Sagnac phase shift resulting from rotation of the coil. The optical fiber coil has a plurality of turns and is formed of at least two separate interconnected coil sections each having a predefined number of turns of fiber. In the gyro arrangement, the separate sections are axially disposed adjacent to each other in such a way that the direction of winding of the turns in one of the coil sections is counter to the direction of winding of the turns in the other of the coil sections. The plurality of turns in each coil section is selected to be such that the sum of the effective lengths defined thereby is sufficient to realize the desired gyro modulation frequency. At the same time, the Sagnac phase shift for a given rotation rate is made proportional to the difference between the effective lengths of the coil sections and remains within a desired threshold level even if the overall effective length of the fiber coil is increased. |
