| 摘要 |
PURPOSE:To enable the considerable expansion of a measurement range without decreasing the sensitivity of measurement, by using light having >=2 kinds of wavelengths as a light source for an interferometer using an optical fiber. CONSTITUTION:The light of the wavelength lambda1 supplied from a light source 1 and the light of the wavelength lambda2 supplied from a light source 2 are changed over by a photoswitch 6. The time chart of the light input to an optical fiber loop 5 is shown in the figure. The interference rays P1, P2 that measure an angular speed are extracted in synchronization with the t0 in the figure (the area where the lambda1, lambda2 are not mixed). The relation between the rays P1, P2 and the angular speed OMEGA of the optical fiber is shown in the figure. Here, the P1, P2 are shown in a standardized form. The measurement range of the angular speed OMEGA is DELTAtheta=-pi-pi and the n in this stage is n=1/2(-1-2/k)-1/2(-1+2/k) at DELTAtheta=ktheta(lambda1). If k=2/7 is assumed in an example, n=-4-3. The measurement range of the theta(lambda1) in this case is (-7/2pi-7/2pi) and the measurement range (-pi/2-pi/2) in the prior part can be expanded by 7 times. The measurement range is thus expanded considerably without decreasing the sensitivity of measurement. |
