Project/Area Number |
03452087
|
Research Category |
Grant-in-Aid for General Scientific Research (B)
|
Allocation Type | Single-year Grants |
Research Field |
物理計測・光学
|
Research Institution | The University of Tokyo |
Principal Investigator |
HOTATE Kazuo The University of Tokyo, RCAST, Associate Prof., 先端科学技術研究センター, 助教授 (60126159)
|
Co-Investigator(Kenkyū-buntansha) |
HIROSE Akira The University of Tokyo, RCAST, Lecturer, 先端科学技術研究センター, 講師 (70199115)
|
Project Period (FY) |
1991 – 1992
|
Project Status |
Completed (Fiscal Year 1992)
|
Budget Amount *help |
¥6,000,000 (Direct Cost: ¥6,000,000)
Fiscal Year 1992: ¥2,300,000 (Direct Cost: ¥2,300,000)
Fiscal Year 1991: ¥3,700,000 (Direct Cost: ¥3,700,000)
|
Keywords | Optical Sensing / Coherent Optical Sensing / Optical Gyros / Fiber Optic Gyros / Navigation / Optical Passive Ring-Resonator Gyro / コヒ-レント光センシング |
Research Abstract |
The purpose of this study is to improve the performance of the optical passive ring-resonator gyro. The methods to realize the specifications for aircraft navigation have been systematically considered. Experimental setup has been constructed to study the countermeasures for performance deterioration factors, such as polarization fluctuation, optical Kerr effect, and thermal drift all in the fiber ring resonator. A novel method to reduce the optical Kerr effect induced drift has been proposed, whose performance has been successfully confirmed in the experiments. In this method, the drift can be distinguished from the Sagnac effect by using simple intensity modulation of the incident light and the synchronous detection scheme. The methods to reduce the polarization fluctuation induced drift have been investigated. The polarization maintaining fiber resonator having 90 degree polarization axes rotation at the splice point has been found to be the most promising method. According to the above studies, the experimental setup has been constructed, which includes the resonator mentioned above, the digital feedback method; the original way to reduce the thermal fluctuation induced drift, and the binary PSK modulation method to reduce the backscattering induced noise. The zero-point stability better than the earth rotation rate have been demonstrated, which is the world wide top performance. Furthermore, a novel method to remove the rock-in problem by using the optical Kerr effect in the resonator has been proposed, and the performance has been experimentally demonstrated. A single-mode fiber resonator with reduction of the polarization fluctuation induced drift has also been proposed and analyzed. Basic studies on fiber ring laser gyro utilizing the stimulated Brillouin scattering in the resonator has been analyzed to found the way to stabilize the oscillation.
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