| 摘要 |
Fiber optical gyro with preferably a laser diode (1) as light source and of which light is divided and fed into both directions of a fiber-optic coil (3). The counter propagating beams thereafter are combined where they were divided and the phase difference is interferometrically detected (2). The phase difference between the two beams, the Sagnic-shift, appears when mentioned coil is rotated. According to the invention the gyro consists of two channels to which light feeds time multiplexed by means of a directional coupler (14), where each channel consists of possibly a polarizer (16), a Y-branch (15) equipped with phase modulators on both arms (17) and a fiber coupler (18), partly connected to each channel, partly connected to one of the ends of the fiber coil (3), and each of the channels together with light source (1), detector (2) and fiber coil (3) constitutes one by itself complete fiber optical gyro, but where the two channels either are modulated differently or are designed differently. According to the invention, further on polarization selective modulation can be used which then is performed at both sides of the optical fiber coil. The signal is then to be detected in at least the eighth harmonic of the modulation frequency. |
