发明名称 |
Optical detector for magnetic fields employing feedback circuitry |
摘要 |
An optical detector for magnetic fields detects rotations in the polarization of a beam of polarized light caused by the magnetic fields. A modulator responsive to a fixed frequency signal introduces a fixed frequency of oscillation in the polarization of the light beam. The output signal of a polarization detector is filtered by a band pass filter and is fed, along with the fixed frequency signal, to a phase detector. The output of the phase detector is inverted and used as a feed-back signal to the modulator to cancel the rotation in polarization caused by the magnetic field. This feedback signal is also the final output signal of the detector.
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申请公布号 |
US4079429(A) |
申请公布日期 |
1978.03.14 |
申请号 |
US19770760475 |
申请日期 |
1977.01.18 |
申请人 |
EASTMAN KODAK COMPANY |
发明人 |
TRAVOT, GUY CLAUDE DANIEL;SIRAND-REY, GERARD RENE"ASTMAN KODAK COMPANY |
分类号 |
G01R15/24;G02F1/09;G11B11/10;G11B23/00;(IPC1-7):G11B5/32 |
主分类号 |
G01R15/24 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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