| 摘要 |
PURPOSE:To detect an angular speed of rotation with extremely low noise without making the oscillation of a laser unstable by providing a spatially different optical path for light projected from or incident to an optical fiber loop, and applying a phase bias to only a light wave propagating the loop in one direction. CONSTITUTION:Linear polarized light projected from the laser 21 is split by a half mirror 22; one beam is transmitted through a phase shifter 26 and birefringent crystal 23, coverged by a lens 29, and entered into the fiber loop 25 from one terminal, and the other beam is transmitted through the other birefringent crystal 24, converged by a lens 30, and entered into the fiber loop 25 from the other terminal. The light transmitted through the optical fiber 25 clockwise and the light propagated counterclockwise and transmitted through the birefringent crystal 23 come together at a position different from the split position and interfere with each other, and the interference light is detected differentially by photodetectors 27 and 28. When the optical fiber loop is rotated, the light waves propagated clockwise and counterclockwise have a phase difference, which is converted into the intensity of the interference light to detect the angular speed of rotation. |
