| 摘要 |
PURPOSE:To make it possible to detect rotating direction and speed accurately, by adjusting the length of an optical fiber for preserving a plane of polarization for synthesis, and changing the phase difference in light beams, which pass in the optical fiber for preserving a plane of polarization in the reverse direction to each other, in a sine wave mode. CONSTITUTION:Monochromatic light from a light source 4 is split into two polarized light beams by a polarization beam splitter 7a. The light beams are inputted to an optical fiber for preserving a plane of polarization 8 having a polarization axis of 45 deg. through collimator lenses 2a and 2b, respectively. The light beams, which are propagated clockwise and counter clockwise directions, are synthesized by the splitter 7a, split into horizontal and vertical polarization modes by a polarization beam splitter 7b, and introduced into an optical fiber for preserving a plane of polarization for synthesis 10 through collimator lenses 2c and 2d and optical fibers for preserving planes of polarization 9a and 9b. By changing a length l of said fiber 10, the interference light intensity, which is proportional to the sine of the phase difference based on the rotating direction of the fiber 8, is obtained. |
