| 摘要 |
PURPOSE:To remove the variation in a scale factor due to the variation in quantity of light, by detecting the magnitude of the DC component contained in the output of a light receiving element by a DC component detection circuit and dividing the magnitude of the modulation frequency component in the output of the light receiving element on the basis of the detection value. CONSTITUTION:The output beam of a light emitting element 1 is divided into two beams by a beam splitter 2 and two beams are incident to terminal points A, B of an optical fiber loop 5 wound a large number of times in a coil form as right-turn beam and left-turn beam while modulation voltage is applied to a phase modulator 6 to change the light path length of the optical fiber and the phase difference DELTAtheta generated in the right-turn and left-turn beams is measured to detect a rotary angle speed. The variation in left-turn and right-turn amplitudes E1, E2 of beams entering a light receiving element 7 through the beam splitter 2 at this time is removed by dividing the magnitude of the modulation frequency component detected by a detector circuit 8 by that of the DC component detected by the DC component detection circuit 10. |
