| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical rotary joint having 0.2 dB or less deviation of a propagation loss by rotation, which performs multichannel measurement simultaneously and infinitely rotates, and also to provide an optical electromagnetic field sensor. SOLUTION: This multichannel high-stability optical electromagnetic field sensor is acquired by acquiring an RF signal having a very small deviation, by compensating deviation of transmission loss generated by rotation of the optical rotary joint, by installing a feedback circuit by the use of light so that the DC level of an intensity-modulated measurement signal becomes a constant value, or providing a feedback circuit of an electric circuit, and by installing an optical multiplexer and a branching filter composed of wavelength filters above and below the optical rotary joint, and performing measurement with laser beams of different wavelengths. COPYRIGHT: (C)2011,JPO&INPIT |
