HIROSE Akira The University of Tokyo, RCAST, Research Associate, 先端科学技術研究センター, 助手 (70199115)
HIGASHIGUCHI Minoru The University of Tokyo, RCAST, Professor, 先端科学技術研究センター, 教授 (30013626)
OKOSHI Takanori The University of Tokyo, RCAST, Professor, 先端科学技術研究センター, 教授 (70010709)
|Budget Amount *help
¥8,800,000 (Direct Cost: ¥8,800,000)
Fiscal Year 1989: ¥2,800,000 (Direct Cost: ¥2,800,000)
Fiscal Year 1988: ¥6,000,000 (Direct Cost: ¥6,000,000)
The purpose of this study is to clarify the manner for increasing the Performance of the Optical Passive Ring-Resonator Gyro, through the experimental studies using the setup having the various countermeasures for performance deterioration factors, and through the detailed analyses on the factors.
First of all, the experimental setup has been constructed having the countermeasures, which we had been investigating. Moreover, the novel method has been invented to drastically reduce the noise caused by the Rayleigh backscattering in the fiber resonator, that has been applied in the setup. The polarization fluctuation in the resonator has been detailedly analyzed as one of the dominant noise factors. Even a small misalignment at the fiber splice in the polarization maintaining fiber resonator has been analyzed to cause a large drift. This drift can be reduced by putting the fiber polarisers at the lead portions of the resonator, or rotating the polarization axis by 90 degree at the splice, which have been estimated detailedly using our own analysis method. Optical Kerr effect has also been observed, at the first time, in the experiment.
Besides the above studies, interferometer applications related have been investigated, such as the optical heterodyne fiber gyro, high resolution reflectometry by synthesis of the coherence function, fiber sensor multi/demultiplication and high performance coherent detection schemes. Requirements from the system including the gyro have also been investigated.
From the above studies, the gyro resolution better than the earth rotation rate and the zero point stability comparable to that rate have been achieved in the experiment, which are in the highest level among the data presented so far, and the countermeasures for the dominant nose factors have been enough clarified. Thus, the purpose of this study has been successfully achieved.