| 摘要 |
PURPOSE:To make it possible to detect rotating directions, by making output light circular polarization once by a 1/4 wavelength plate, thereby changing the output of a differential amplifier into a positive or negative value depending on the rotating directions. CONSTITUTION:A half of laser light from a light source 1 passes a BS (beam splitter) 3. The S polarization component and P polarization component of the linearly polarized light in the bearing of 45 degrees are reflected by and transmitted through a PBS (polarized light beam splitter) 5. When a plane of polarization preserved optical fiber coil 9 is not rotated, the phase difference between the transmitted light in the counterclockwise direction and the transmitted light in the clockwise direction is equal, and the light taken out of the BS3 is linearly polarized. When a 1/4 wavel length plate 10 is placed at the bearing of 45 degrees, the output light becomes the circularly polarized light. In a PBS11, the polarized component is taken out, the output of a photoelectric transducer 12 is guided to a differential amplifier 13, and the output is observed. When the plane of the polarization preserved optical fiber coil 9 is not rotated, the output is zero. When the coil is rotated right and left, the output having the positive or negative polarity appears. By integrating the differential amplifier 13, the direction from the initial state can be found. |
